ROUNDABOUTS Old idea for traffic returns full circle

Traffic lights wouldn't be needed where roundabouts are located.
KNIGHT RIDDER NEWSPAPERS
WASHINGTON -- To reduce traffic congestion and get vehicles through intersections faster and more safely, some traffic engineers are very excited about an old idea.
Take out the traffic lights, they suggest. Instead, move vehicles around a central circular island continuously at low speeds. Require drivers who are entering the circle to yield to those who already are in it.
They're called roundabouts these days, a Britishism that's meant to distinguish the updated concept from the primitive traffic circles or rotaries that your grandfather swore his way around.
From Scandinavia to Sydney, Australia, the improved versions work like a charm, proponents say, and they could in the United States, too.
Like spinach and recent Democratic presidential candidates, however, roundabouts are easier to endorse than to like. So far, U.S. highway departments have built only about 500 new-style roundabouts, although advocates say that at least 26,000 major U.S. intersections would benefit from them.
Although they've been hooted down in some cities, roundabout backers remain unbowed, some noting that Americans for years disdained another European standby --bottled water.
Fewer crashes
A recent institute study by the Insurance Institute for Highway Safety, a research group for insurers, found that crashes typically drop by 40 percent or more when roundabouts replace traditional right-angle intersections governed by traffic lights.
The number of crash injuries at roundabouts drops even more dramatically because roundabouts eliminate right-angle collisions, which are the most dangerous after head-on collisions.
In France, new roundabouts reduced crash injuries at intersections by 78 percent, according to a 2002 study. In Austria, they dropped 87 percent.
"There's nothing that we can do in traffic engineering that's anywhere near as significant as this," said Richard Retting, senior transportation engineer at the highway safety group, based in Arlington, Va.
Fuel consumption and air pollution also drop sharply, according to Retting, thanks to reductions in traffic delays of 40 percent or more when roundabouts replace conventional intersections.
In a recent analysis of 10 busy signal-controlled intersections in nearby Washington suburbs, Retting projected that roundabouts would save 300,000 hours and 200,000 gallons of fuel a year.
"If I had to commit the remainder of my career to one safety factor, it would be this," said Retting, 45, a leader of the national roundabout campaign.