January 25, 2008

U.S. transportation planners take roundabout route

Right-angles disappearing in favour of European design

ALBANY, N.Y.

New York drivers are increasingly finding themselves going in circles, and it’s not because they’re lost.

Following a U.S. trend, state transportation planners are actively turning right-angle intersections into roundabouts, derided by many but proven in a national study to be safer than some intersections with stop signs or traffic signals.

Traffic circles have long been part of New York roadways, but modern roundabouts are distinctly different. Today’s roundabouts are much smaller than older traffic circles — about 30-60 metres in diameter compared to about 120-180 metres — and they’re designed with narrow lanes that force drivers to slow down.

Transportation planners say the newer design — which originated in Europe and found its way to the United States around 1990 — results in improved traffic flow and fewer accidents.

“The No. 1 reason we’re doing these is safety,” said Howard McCulloch, a traffic engineer with the New York State Department of Transportation who specializes in roundabouts.

At intersections with stop signs or traffic lights, the most common — and serious — accidents are right-angle, left-turn, or head-on collisions that can be severe because vehicles may be moving fast. Roundabouts virtually eliminate those types of crashes because vehicles all travel in the same direction.

Roundabouts also tend to keep cars moving steadily in all directions. That cuts down on fuel-wasting stop-and-go traffic and reduces air pollution, giving planners another reason to use them, said Wade Scarbrough, a roundabout specialist with Kittelson & Associates, a transportation engineering and consulting firm in Portland, Ore.

“There are times when there’s such a huge amount of traffic that they get backed up, but for the most part, it’s a steady flow,” Scarbrough said.

The U.S. Federal Highway Administration — which oversees federal money spent on highway construction and maintenance — estimates 150 to 250 roundabouts are being built each year and supports a goal to raise that to roughly 1,000 per year, said Doug Hecox, an agency spokesman.

“We do recognize this as a very valuable tool,” Hecox said. “In many circumstances, they’re a safer alternative.”

Since New York started its roundabout-building program in the late 1990s, it has installed them at 42 intersections, and the projects often meet with stiff community resistance, McCulloch said.

“I’ve seen people who are pretty level-headed get really emotional,” he said.

The exact number of roundabouts in New York, or U.S.-wide, is unclear since no single state or federal agency keeps track of them all.

Richard Retting, a transportation engineer with the Insurance Institute for Highway Safety, estimates about 1,000 have been built so far, and the pace is accelerating as 23 states from Alaska to Florida have active roundabout construction programs.

Roundabout proposals frequently evoke strong opposition from drivers, but those opinions quickly change when they become familiar with them, Retting said.

An Institute survey in three communities where roundabouts replaced stop-sign intersections found 31 per cent of drivers supported the roundabouts before construction, compared with 63 per cent shortly after they were built.

McCulloch attributes much of the opposition to roundabouts to people confusing them with the older traffic circles and the consternation that they can sometimes cause drivers.

Corrine Weeks, a teacher from Voorheesville, N.Y., who said she became quite familiar with roundabouts during an eight-month sabbatical in England in the late 1980s, doesn’t like driving through them.

“I just find them very uncomfortable,” she said. “You have to constantly be looking over your shoulder, and it just doesn’t feel safe to me having to basically guess what the other person is going to do.”

William Hotaling, a former public works superintendent from the village of Voorheesville, was one of the most vocal opponents and led a campaign against the state’s plan to put a roundabout in his community.

Nearly five years later, Hotaling grudgingly acknowledges the roundabout works the way transportation planners said it would. “It’s not very attractive to look at, with the signs all around it,” he said. “But does it work? Yes. I can’t argue with that. It does slow people down.”

That slowing and the traffic “calming” that roundabouts create are largely why they’re so much safer than other types of intersections, Retting said.

An Insurance Institute study of 24 intersections before and after roundabouts found the new device reduced the number of injury-causing crashes by 76 per cent and crashes that caused fatal or incapacitating injuries by 90 per cent.

Some communities worry that drivers will avoid roundabouts, pushing more traffic to adjacent streets.

Both the state Transportation Department and the Federal Highway Administration rely largely on Insurance Institute roundabout research, and the group hasn’t analyzed the effect roundabouts have on traffic volumes.

However, its crash study includes figures that show average daily traffic either rose or stayed about the same after the roundabouts were built.

Associated Press

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