What happens when we redesign the human habitat to take walking out of daily life? Over 35 percent of Americans are now clinically obese. That's partly because of diet, but also because we've designed our cities for cars.
Cities have policies that sound good on paper, calling for mixed-use development and walkable neighborhoods, but they also have detailed technical design requirements that don't let that happen. Instead, we end up with typical sprawl: it's actually illegal to build anything else. In every city where I've worked, if everyone's favorite walkable neighborhood burned to the ground, the local rules wouldn't let us rebuild it.
What we do build is not only less economically successful, and more congested, and more polluted, it's also going to kill us. Sprawl leads to more traffic accidents, and shorter life expectancy.
Sprawl also makes us angrier; road rage is now a clinical condition. As social primates, we get an enormous amount of information from body language and eye contact. Walking down a packed sidewalk, pedestrians don't run into each other even though they're not signaling turns. We know through the slightest tilt of the shoulder or flick of the eye that someone's changing direction. If you do accidentally bump someone, a dip of the shoulder is enough of an apology. But all of the complexity of our social world is lost when you're in a car. There's no way to know if someone who cut you off is sorry or trying to mess with you.
When you get cut off, the brain releases an array of chemicals that make your muscles tense, make you less likely to think through the consequences of actions, and trigger the release of even more chemicals. It literally drives us crazy. It's ok if it happens once in a while, but if the amygdala is constantly firing off a toxic soup of chemicals, it creates permanent changes in the brain that make you mistrustful, angry, less able to handle complex reasoning, and more antisocial. If we have any hope of creating a more civil society, a thriving democracy, we can't have people trapped in their cars every day.
Walking and biking, on the other hand, not only make us fit, but they also both improve mental health. Oxytocin—the same chemical released during sex and breastfeeding, that reduces stress and increases trust and empathy—is released during outdoor exercise. (Indoor exercise, interestingly, doesn’t have the same effect).
When we know that driving makes us fat, sick, dumb, mistrustful, and more likely to die early—but walking makes us fitter, stronger, better able to handle complex reasoning, more loving, and more trustful, why are we in the transportation world spending all of our effort designing around the needs of the car and not walking or biking? When we know the effects of driving on climate change, how could there be any argument?
There are many things that need to change in urban planning and design, but one of the most basic is this: we need to define success differently. Right now, engineers make many decisions based on something called "level of service"—basically, how long cars are delayed at certain points. Our goals should be based on people, not cars. Right now, a busy commercial street would be judged a transportation failure even though it’s a social and economic success. We need to change the way we measure, so designers can make the right decisions.
Design can make it more delightful to walk than drive, so people don’t want to jump in their cars for errands. Design can make it safer to bike so everyone feels comfortable on the street, not just hardcore cyclists. Design can make public transit fast, reliable, dignified, and sociable. And design can make neighborhoods beautiful, so people are inspired to protect and maintain them. Design decisions might have created sprawl, but they can also rescue us from it.
Sprawl photo via Shutterstock