99% Invisible - 99% Invisible-68- Built for Speed

Episode Date: December 12, 2012

I want you to conjure an image in your mind of the white stripes that divide the lanes of traffic going the same direction on a major highway. How long are the stripes and the spaces between them? You can … Continue reading →

This is 99% Invisible. I'm Roman Mars. I want you to conjure an image in your mind of the white stripes. Not those white stripes, but the white stripes that divide the lanes of traffic going in the same direction on a major highway. How long are those stripes? You can spread your arms out to estimate if you want to. Over the course of many years, a psychology researcher named Dennis Schaeffer at Ohio State asked students from many different parts of the country this question. And the most common response was two feet. So if you're like most people, you estimated that those white stripes are two feet long,

maybe a little more. But if you did, you'd be very, very wrong. This is Tom Vanderbilt. My name is Tom Vanderbilt. I'm a writer in New York and author of Traffic Why We Drive the Way We Do and What It Says About Us. Every three pages of Tom's terrific book traffic, I can probably turn into a 99% of his episode, but back to the highway. Well, early on in my research, I was talking to a highway engineer and he said, if your car is ever broken down on the side of the road,

we've ever been forced to get out of your vehicle on a highway. Just take a moment to notice what a strange landscape it is. If you're happy to be standing near a road sign, these road signs are huge. I mean, they're not meant to be experienced as humans on foot, they're meant to be experienced at 75 miles an hour.

With the clear view typeface. Perfectly visible, retro reflective. And then there are the white stripes. If you actually kind of got out of your car and were able to walk on a closed highway and walk from one end of those stripes to the other, you'd find that, I mean, years ago in the United States, the highway standard was fifteen feet long

which is longer than car itself current federal highway administration guidelines suggest a length of ten feet with thirty feet between the dashes that's something that that is shocking to people and remember most people in the shape of study said that those stripes were two feet long that's such a vast

culture between it's not you know it's not sort of like said that those stripes were two feet long. That's such a vast gulf there between. It's not sort of like, they're actually five feet without they were two margin of error kind of thing. And it goes back to this fundamental point that when you're in a car at high speeds, you're experiencing only a sense of the landscape rather than the actual landscape. This kind of sense of landscape has been presented to you to essentially make you feel comfortable.

And to make a highway work at what are really evolutionarily ridiculous speeds for a human to travel. You have this big, flat, wide open, kind of stretch of road that even if you have a 65-mph sign, the message of the road is telling you something entirely different. I think that's really where a lot of our behavior comes from. Sometimes you have sort of willful speeding, willful kind of law breaking,

but a lot of it is just people are paying attention to the visual messaging of the road, not to their speedometer. Long dividing lines and clear vistas, give the illusion that you're going at a reasonable speed, as soon as something encroaches into view, you get a sense of how fast you're going. That's one reason why those temporary concrete walls that crews put up right next to the road during construction are so unnerving. The error in perception of white striped length

is attributed to the fact that when we drive on the highway, we tend to look so far ahead that we usually only experience the dashes and gaps when they are very far away in an angle where they look shorter. But there's no consensus as to why people all over the country were so consistently wrong with the two-feet estimate. It's, yeah, become my favorite, one of my favorite cocktail party, you know, facts. Mine too. Stump the driver with this white stripes information. I don't want to leave you with the impression that the white dividing lines are uniform though.

You won't find, you know, 10 foot highway lines on a, say, a boulevard in New York City. And you probably won't find 10 or 15 foot stripes on bridges or highway on ramps. Or let's hope you don't because that's an entirely inappropriate design language for that space. Limited access highways are designed for a very precise purpose. There's the highways meant for uninterrupted fast flowing traffic. Get people from point A to point B, it's quickly as possible with no interruptions. I mean that sort of environment does not work in cities or suburbs. The problem is when that approach is grafted into

places where it doesn't belong. I think we're actually kind of paying the price for this right now in some suburban environments where you find these kind of arterial highways that were built almost an engine highway engineering standard with again these long sightlines, wide roads encouraging people to go fast and then we went and built all kinds of development along those arterial highways which was never really supposed to be there but with so many people driving on these roads they became absolutely irresistible to commerce. This is kind of the new American Main Street, right, where you have your Costco's and your

your fast food and all sorts of in and out parking lots, driveways, drive-throughs. Yet people also going very fast and kind of Eric Dumbaw does a lot of research suggesting that these are really some of the most dangerous places to currently drive in America, not crowded urban cities, which is what a lot of people would think. The whole approach is called the forgiving road. The idea was that, you know, to first try to minimize the potential that a crash could happen through, again, through lack of obstacles, you know, generous sightlines, all these sorts of things.

But then if crash did happen to kind of mitigate the effects of what would happen to not punish the driver for the mistake that he will inevitably make. This was I'm quoting some of the language from the time. So you see that nowadays in things like in California, you'll have your guardrails that are sort of wire guardrails that if car strikes that guardrail tends to catch on the guardrail rather than being bounced back out into traffic, which causes another series of collisions. So this forgiving road is a positive thing in terms of good safety engineering. But they were so sort of seduced by it that the call was made to bring it into

even the surface street network. So things like street trees began to be deemed hazards by engineers, just outright hazards. I mean, that makes sense on a high-speed country road, but if you're talking about residential street, we're not supposed to be going more than 25 anyway, is the presence of a street tree in the side of the road where it's providing shade

and comfort to pedestrians, is that the same sort of hazard? Is it even a hazard at all? The conclusion many planners came to was, yes, trees are a hazard. You find pre-war suburbs, you have the street, a set of trees, and then the sidewalk. Coast war, this sort of shift began to happen

where the trees removed on the other side of the sidewalk. Suddenly pedestrians were put into the position of being the buffer between drivers and those menacing trees. There was sort of a pernicious thing that happened here is that, you know, as you move those trees away, the visual sensation of the road became wider. And if there's one kind of iron law of traffic engineering, it gets into this visual perception thing as well. The wider a road is or is perceived to be the faster driver speed tends to increase. And of course, you know, the final,

if you look at sort of 1990s era, you know, the suburbia that they just kind of eliminated the sidewalk and the trees altogether. So that was sort of the final solution, just to eliminate any kind of hazard. And Tom Vanderbilt says you can almost date a subdivisions development based on that shift. a subdivisions development based on that shift.

This points to one of the problems about road engineering is that humans tend to consume the extra engineering measures that have been built in for their safety. Much in the same way I like to draw the analogy with some of the research that's been done on food packaging by Brian Wandsick at Cornell University. You're doing experiments where, you know, if you give people, just random group people, large buckets of popcorn filled to the top with popcorn and give them a smaller amount of popcorn in a smaller package, they'll just eat more of the larger package, whether they're,

it has nothing to do with their level of hunger. It's just the size of the package influences their behavior. And I think a lot of our road environments are sort of like that. They're over engineered for this safety. And then we tend to consume a lot of the extras, getting us back to this kind of homeostatic edge that we're always kind of playing with, I think. 99% Invisible is Sam Greenspan and me Roman Mars. It's a project of 91.7 local public radio, KALW in San Francisco, and the American Institute of Architects in San Francisco. You can find the show and like the show on Facebook. happens as go. You can find this show and like the show on Facebook.

In fact, that's where a lot of the discussion and interaction happens. So join us over on Facebook. We're getting pretty close to 10,000 likes, which I would really enjoy. I tweet at Roman Mars, and we have links to all the stuff that we've been talking about in this episode at 99%invisible.org. Oh, one more thing. I and every other creative audio lover owes a huge debt to the Third Coast International

Audio Festival. And every year I send them a little something to make sure that they keep going or I buy a T-shirt and they have hands down my favorite T-shirt design in the whole world across the front is the word listen written in braille. I have like six of them in every color. It's a must-have for any radio lover. You can find out the various ways that you can support the Third Coast International Audio Festival at 3rd Coast Festival dot org. at 3rd Coast Festival.