Nowhere for cars in downtown Chicago to go — even with green lights.

Nowhere for cars in downtown Chicago to go — even with green lights.

Credit:

Tripp/CC BY 2.0

Americans spend an average of 40 hours stuck in traffic each year. Which, according to one study, translates into 120 billion dollars of wasted time and fuel.

That creates a huge amount of pollution — more than that produced by the entire country of Estonia.

But Brian Wolshon secretly loves traffic.

“Even traffic jams I find interesting,” says the associate professor of engineering at Louisiana State University. “Because I'm thinking about what's going on here. What are the causes? Weaving, an incident? How long do I stop and how fast do I go?”

Wolshon is one of many traffic engineers to acknowledge our roads are inefficient. People sometimes ask him why it's hard to improve something as low tech as a painted strip of asphalt. The truth is that traffic engineers already know pretty well why our roads are inefficient. The reasons are habit, design, and data.

As drivers, we can be irrational. We usually think we're stuck in traffic. When in fact — we ARE traffic.

Even society's habits reduce efficiency. Ever since we standardized the 9 to 5 workday, drivers have sat in rush hour.

“When we design roads, we're really trying to design it for 2 small parts of the day,” Wolshon says. “That means that 22 hours of the day, that road is really built above capacity.”

The problem is, inefficient design gets permanently etched into our cities. Most urban areas lack the space for new roads and wider lanes. So we're stuck with infrastructure we inherited from our grandparents.

When it comes to data, traffic engineers have updated roads based on inaccurate surveys of driver habits. Only recently have cars become data points that drive traffic improvements.

At hundreds of major intersections in Boston, for example, sensors count vehicles and cameras observe congestion. Live video of traffic flashes across screens in the Traffic Management Center, on the 7th floor of Boston City Hall. John DeBenedictis directs engineering for the city's Transportation Department.

“Most people probably don't think there are eyes and ears keeping track of all this stuff,” DeBenedictis says. “We impact a lot of people's lives whether they know it or not.”

Employees here type commands into computer terminals...and instantly change the timing of an intersection's red and green lights. Drivers rarely notice it. But Boston's engineers do this more than 100 times per day. “We're not trying to speed traffic—we're trying to make it move more efficiently, with fewer stops.”

In the traffic world, better data may be the future. An MIT professor named Marta Gonzalez has found new insights about traffic in our cell phone records. They told her precisely how people move through a city.

“There are digital traces that are everywhere in our cities,” Gonzalez notes. “It's like the pulse of the city. The x-ray of the city breathing.”

The data pinpointed two specific commutes that clog the system. Gonzalez says it's about time that we make traffic engineering higher tech. “We are so used to making everything fast in terms of information—but we are still stuck in traffic.”

You can see one reason just outside Marta Gonzalez’s office. Cars whiz across a bridge and onto crowded Massachusetts Avenue. Gonzalez says that every once in a while, repairs shut down the bridge. When that happens, all the nearby bridges clog up. Traffic jams ripple through downtown Boston.

In other words: traffic is never just a local problem. And local solutions — like tweaking stoplights and widening roads — have unpredictable effects on the whole system.

Some “solutions” even backfire. Let's say an engineer relieves traffic on a major road. That could make everyone's drive shorter... “or, conversely,” says Wolshon, “it just means we can put more cars on that road that we already have. This concept of: if you build it, they will come.”

This means engineers can't fix the whole problem. If you really want to avoid traffic... you might just have to stay off the road.

This story first aired on PRI's Innovation Hub.

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