Maryland officials thinking of shrinking traffic circles

Success in Towson, elsewhere may breed smaller roundabouts

April 16, 1999|By Liz Atwood | Liz Atwood,SUN STAFF

A few years ago, roundabouts seemed the biggest thing in traffic engineering. Now, state highway officials are thinking small.

Flush with the success of 13 traffic circles in Towson, Columbia and elsewhere in the state, officials want to introduce "mini-roundabouts," with islands as small as 6 feet across, compared with the 40- to 188-foot islands in more typical roundabouts.

The small traffic circles -- used in England for many years -- could fit into a three- or four-way intersection and cost a fraction of the $150,000 to $600,000 price tag for the larger roundabouts.

While sites have not been selected, officials are considering interchanges in Brookeville in Montgomery County, where traffic is congested and space is insufficient for traditional roundabouts, said Tom Hicks, director of the State Highway Administration's Office of Traffic and Safety.

"Roundabouts are starting to catch on," Hicks noted. "But not everyone believes in them."

Hoping to dispel the doubts, Maryland transportation officials and their counterparts in Vermont and Michigan invited a British expert on mini-roundabouts to give lectures in the United States explaining how mini-roundabouts work.

"Highway authorities are wasting a lot of money installing, running and maintaining traffic signals," engineer Clive Sawers told a room full of traffic and highway engineers at the State Highway Administration offices on Dorsey Road recently. "Roundabouts, once installed, tend to operate perfectly satisfactorily with very little maintenance."

While some Maryland motorists have had trouble adjusting to the concept, Hicks said roundabouts have proven effective in handling traffic safely. In five roundabouts for which the state has sufficient data, accidents declined 63 percent and injury accidents dropped by 86 percent after the circles were installed.

The decline in accidents has been more dramatic at the $2 million Towson roundabout through which 28,000 vehicles pass daily.

In 1996, before the roundabout opened, 18 major accidents were reported at the intersection of York, Joppa and Dulaney Valley roads and Allegheny Avenue, nine involving injuries, police said. As of December -- almost a year after the roundabout opened -- the number of accidents had dropped to five, with one serious injury.

Mini-roundabouts can serve tight intersections and -- at $30,000 to $50,000 apiece -- are about half the cost of traffic signals, Hicks said.

Howard County introduced a similar small design two years ago to slow traffic on Shaker Drive through the Village of Kings Contrivance. But with islands 18 feet in diameter, they are large compared with what the state is considering.

Sawers, who has designed and written a book about mini-roundabouts, urged highway officials to give mini-roundabouts a try at intersections where congestion and safety are problems.

Armed with a laptop computer that handily reversed photos and drawings of British highways into illustrations the right-lane-driving Americans could understand, Sawers explained traffic flows around the tiny circles.

In Great Britain, he said, mini-roundabouts have been used for nearly 30 years, lowering the accident rates while accommodating up to 7,000 cars an hour in a four-way circle, he said.

The English have decorated the small islands with sculptures and plantings, he noted.

Sawers chastised Americans for being afraid to try new ideas for fear of lawsuits.

"You kill 42,000 people a year [in traffic accidents], and you say this is experimenting with people's lives?" he asked.

During his presentation, Sawers had to struggle not only with remembering that Americans drive on the right, but with a language barrier.

When he explained how mini-roundabouts reduce the problem of "rat chasing," his listeners smiled blankly. "Oh, what do you call it when people go off the main highways and go through the neighborhoods?" he asked.

"Cut-through traffic," someone told him.

Likewise, his audience was perplexed when Sawers spoke of "shunting," which the Americans figured out meant rear-end accidents.

Sawers, who last visited the United States 30 years ago, said he had to brush up on his American English before his trip. "I read a lot of books," he said.

For the most part, he remembered that American motorists "yield" rather than "give way," although he still spoke of "queuing up" and "carriageways."

But while the language differences presented amusing moments, the American engineers seemed more perplexed by the British notion that pedestrians don't have the right of way and wondered how sport utility vehicles could navigate in a traffic lane 6 feet wide.

Sawers visited several Maryland roundabouts during his visit, including the one in the center of Towson.

"I was very impressed with it," he said. "It was nicely landscaped, and it used a lot of features I would have used."

Pub Date: 4/16/99

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