There’s a scene in the 1985 slapstick comedy “National Lampoon’s European Vacation” where the hapless Clark Griswold, played by Chevy Chase, gets stuck in a traffic circle in Central London and can’t figure his way out. “Hey look kids, there’s Big Ben, and there’s Parliament,” he says excitedly, before repeating the line, over and over, as he keeps driving around, unable to exit.
This broadly reflects American sentiment about roundabouts: They’re confusing and don’t belong on this side of the pond. But traffic engineers say such resistance is short sighted. Not only do modern roundabouts (which differ in size and design from rotaries and large traffic circles) drastically cut traffic injuries and deaths, but, because traffic flows through them without the stop-and-go of red lights, they’re linked to lower greenhouse gas emissions. Also, because roundabouts don’t require lights, they function when the power cuts out after storms.
As I wrote this weekend, no American city knows this better than Carmel, Ind., an affluent suburb of Indianapolis and the roundabout capital of America. Carmel is home to 140 roundabouts and counting, and has just a dozen or so four-way stoplights left.
Jim Brainard, the seven-term Republican mayor who’s responsible for the city’s roundabout building spree, installed them for largely safety reasons, but says the carbon savings are an added plus. Studies of emissions at roundabouts vary by location and time of day, but federal highway officials say the reduction can be significant, and a former city engineer for Carmel estimates each roundabout saves 20,000 gallons of gas a year.
There are about 7,900 roundabouts in the U.S., and though hundreds more are built every year, many traffic engineers would like to see far more. Maybe it’s time for Clark Griswold to give them another whirl.
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