Best of 2019: Two Photos Reveal Why the Key to Slowing Traffic is Street Design, Not Speed Limits
The article below was not merely our most-read Strong Towns post of 2019. It was our most-read post by almost a factor of 5. Of course, that’s the nature of online publishing: you don’t ever know what is going to find viral reach and popularity until it happens. But it’s also true that this post—and more importantly, the meme it centers around and explains, created by our good friend Wes Craiglow back in 2015—does something that is absolutely at the core of what we’re trying to accomplish with Strong Towns.
A few years into the Strong Towns project, it was clear to us that if we only spoke to, or consulted with, professionals—planners, city administrators, civil engineers, and so forth—we would never produce the kind of vast, systemic change we need in how America’s cities and towns are built. We needed a groundswell of cultural change: a mass movement that could lead a bottom-up revolution.
Creating this groundswell means helping people who aren’t planners or engineers or architects realize that, nonetheless, they too are experts in the built environment. That means you too. All of us have our own kind of expertise, because we experience and have to navigate that environment every day.
We’ve all had the experience of driving slowly and cautiously down a street because the environment feels a bit unpredictable or the space feels constrained. We’ve also all had the experience of, despite our better judgment, catching ourselves zooming down a wide open street that feels like you could land a 747 on it. We don’t need to be taught to understand that street design affects our willingness to behave in risky ways—and consequently not just our own safety but the safety of every other person we encounter while we’re behind the wheel. We all understand this, from our own experience.
And yet we often need to be freed to realize that we understand it. And to stand up to the credentialed experts whose claim to authority—”Trust us, it meets the standard”—buttresses business-as-usual practices that have given us an America in which cars kill as many people each year as firearms… yet are not treated as remotely the same level of public health emergency.
What Craiglow’s meme does is take a simple but vital insight about how our world is designed, and how that design affects all of us, and packages it in a highly visual and immediate way that is accessible to nearly anyone. It teaches you to see your city. Once you’ve seen it, you start to see it everywhere you go.
And then, once you can’t unsee it, our hope is that you go out, in your own place, with your own unique talents and expertise, and you demand better. And you create better. Whether it’s streets that naturally #SlowTheCars without the need for constant and costly speed-limit enforcement, or neighborhoods that allow people to bootstrap their way to a bit of wealth, you are the ones who are going to demand it. You are the bottom-up revolution. –Strong Towns staff.
The cost of auto orientation—designing our towns and cities around the easy, fast movement of cars—is not just measured in dollars and cents. The number of U.S. traffic fatalities in 2017 topped 40,000 people. Nearly 6,000 of those people were on foot—a 25-year high. Each of those people had a unique story. Each of them had a family.
And after each high-profile crash, we all hear the same litany of advice from law enforcement and traffic safety professionals.
“Be hyper-aware of your surroundings.”
“Always obey the speed limit.”
“Speed is a factor in 30 percent of crashes.”
“Safety is a shared responsibility.”
And yet, we know that people are sometimes going to make mistakes. Even conscientious drivers make mistakes. People walking, going about their business, are going to make mistakes. No one is going to be hyper-vigilant every moment that they’re out in the world. And why should we have to?
We can't regulate our way to safety. We must design our streets to be safe.
Two simple photos reveal what it means to design a street to be safe, versus counting on the speed limit alone to do the job. This meme was created by planner Wes Craiglow of Conway, AR, and shared on social media by the "Transportation Psychologist," our friend, Bryan Jones. We first shared it back in 2015, but it remains timeless, so here it is again:
As Wes points out: "The meme is intended to help viewers consider how different street designs makes you feel as a driver, and ultimately affect how you behave behind the wheel. Generally speaking, as depicted by the lower photo, narrower travel lanes, shorter block lengths, and a tree canopy, all contribute to drivers traveling more slowly. Conversely, wide lanes, long block lengths, and open skies, as seen in the upper photo, communicate to drivers that higher speeds are appropriate.”
Look again at the two photos. Imagine yourself behind the wheel of a car on each street. On which street would you drive faster? On which street would you exercise more caution?
“Forgiving” Design is a Misnomer
The first photo looks like tens of thousands of suburban streets all over America. It’s entirely representative of something the transportation engineering profession calls “forgiving design.” The premise is simple: drivers will make occasional mistakes—veer a bit out of their lane, fail to brake quite hard enough—and if the street is wide, with high visibility in all directions, and free of immediate obstacles such as trees and fences, those mistakes won’t be catastrophic.
The problem: this street feels too forgiving to a driver. Too safe and comfortable. So drivers speed up. The engineers didn’t account for this aspect of human psychology.
This residential street is built like a four-lane highway, and so even though its legal speed limit is 20 miles per hour, it’s no surprise when somebody guns it up to 40 miles per hour or more down a street like this. It feels natural to do so. It feels safe. But it isn’t safe—because on a city street, unlike a freeway, there might be people around. People who will most likely be badly hurt or killed if a speeding driver hits them.
The Paradox of Street Design: If It Feels a Bit Dangerous, It’s Probably Safer
The second photo, on the other hand, represents the most basic, frugal approach to designing a street for slow speeds. It’s not perfect. It lacks sidewalks or bicycle facilities, which some of our readers might take issue with—and yes, many places ought to have those things.
But this “slow street” does something really profound and important. It causes drivers to slow down, whether or not there’s a posted speed limit or law enforcement is present, because of the uncertainty and sense of heightened risk.
The street is narrow. Visibility is limited—look at that front left corner of the intersection, where a red fire hydrant stands next to a white fence. The lack of visibility there is not a safety hazard: paradoxically, it’s probably the single biggest thing that promotes safety at this intersection. Because if you’re driving here, and can’t see whether a vehicle is approaching from the left, what are you going to do?
That’s right. You’re going to slow down.
Why 20 Miles Per Hour?
If we could keep most urban traffic to 20 miles per hour or less, we could eliminate the vast majority of deaths from car crashes in our cities and towns. We wouldn’t eliminate mistakes—people, both inside and outside vehicles, are going to make them—but those mistakes would rarely be deadly.
The place for wide lanes and “forgiving design” is on a high-speed road. City streets, on the other hand, should be places for people. We know how to design streets that will slow down traffic automatically, without the need for heavy-handed enforcement, and regardless of what the speed limit sign says. We just need to do it.
Read Chuck Marohn’s article on the crucial difference between a street and a road.
Learn more about our Slow the Cars campaign.
Like this content, and want to help us produce more like it? Become a member of the Strong Towns movement, and support Strong Towns’s work to make our streets safe, welcoming, and productive places for people.