More Roads May Pave Way To More Traffic

On Friday, the city of Los Angeles will be closing one of its main freeways, Interstate 405, for 53 hours, from Friday night to Monday morning.

It's part of a billion-dollar widening project that Los Angeles hopes will ease chronic traffic jams on the 405, but many residents, fearing the worst, are already dubbing it "Carmageddon."

For decades, urban areas across the country have been adding lanes and building roads in an effort to fight congestion, but a recent study by the University of Toronto says that these tactics aren't actually all that effective.

The study looked at the largest metropolitan cities in the U.S. and found that widening and building more roads actually creates more traffic.

"What we found was that in cities where there was more roads, there was more driving," economist Matthew Turner, a co-author of the study, tells Weekend on All Things Considered host Guy Raz. "In particular, if you had 1 percent more roads, you had 1 percent more driving in those cities."

Turner's study took into account public transportation, but a city's amount of public transportation didn't make a dent in congestion problems.

"As you increased a city's stock of light rail or bus cars, that there's no impact on the amount of driving," Turner says.

Although that may sound surprising, he says, it's a logically consistent with the study's data on driving. "As you add roads to a city those roads get filled up. There are people waiting to use that capacity. The result on transit is almost exactly the opposite of that."

Ultimately, Turner's research has shown that the only way to deal with congestion is to follow the lead of countries such as London, Singapore and Stockholm, which have incorporated congestion pricing into their city infrastructures. Turner says Stockholm, specifically, has seen a 50 percent reduction in travel time at peak times because of tolls.

Turner admits that it may be hard for drivers to get used to the idea of paying for something that they are used to getting for free, such as the right to drive on a particular road, but he says that the extra charges will be worthwhile in the end.

"We have enough experience with these programs now to know that they really work," Turner says. "In response to pretty small fees, you see big reductions in travel time."

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