As metro Atlanta searches for more ways to solve
its traffic tie-ups, governments are reaching for
lessons from across the pond.
The latest solution is to keep traffic moving,
It is the roundabout, popular in Europe.
Cobb County is considering building its first
roundabouts, in the western section of the county on
Villa Rica Road, which handles nearly 11,000
vehicles per day.
The single-lane roundabouts proposed for west Cobb
would have a diameter of about 115 feet and cost
close to $1 million, including acquiring rights of
way. They would be financed by the county's 1
percent sales tax approved by voters in 2005, county
County officials are testing public sentiment about
installing two roundabouts on Villa Rica, one at
West Sandtown Road and another about 150 yards east
at Irwin Road.
"The roundabouts are safer than traffic signals,
and they operate as efficiently," said Joe Fletcher,
a Cobb traffic engineer, who made a presentation
recently in the west Cobb neighborhood.
Anne Guerrero, who lives off West Sandtown, wasn't
buying the concept. She drives the intersection at
least twice most days, and sees the traffic on Villa
Rica is nearly double that of West Sandtown.
"The dominant flow will control the circle," said
Guerrero. "They need to put a light in there."
But another commuter was more open to the idea.
"It seems like traffic would flow better. I'd lean
toward a roundabout," said David Gallion, who lives
in a subdivision off West Sandtown.
DeKalb County put in a roundabout on North Decatur
and Lullwater roads, and is moving forward on
another at North Decatur and Oxford Road, at the
entrance to the Emory University campus.
Atlanta has installed smaller versions on Peachtree
Hills Avenue, more to slow traffic than regulate
intersections. A roundabout is the focus of Smyrna's
rebuilt town center, and a few smaller circular
islands dot subdivisions and shopping centers.
The state has built roundabouts in Douglas and
Dawson counties. Both are fairly new.
Proponents cite a 39 percent decrease in total
crashes, with a 76 percent reduction in serious
crashes and a drop of 89 percent in crashes that are
fatal or produce incapacitating injuries.
The statistics are drawn from a federal study of 24
roundabouts that replaced traffic signals or stop
Critics claim multiple-lane roundabouts lead to
more side-swipe accidents and that roundabouts can
be disorienting, especially for new and elderly
drivers. After installing roundabouts, Columbia,
Mo., posted instructions on its Web site telling
motorists how to negotiate the traffic device.
The west Cobb roundabouts would replace a four-way
stop at Villa and West Sandtown, which carries about
6,000 vehicles each day, and a stop sign on Irwin
Road, which sees about 4,000 vehicles daily. A
street from a subdivision under construction also
will dump traffic onto Villa Rica across from Irwin
and flow into the circle.
The Villa Rica/West Sandtown intersection is at its
worst in the evening when west-bound traffic on
Villa Rica can back up for 500 yards and spill onto
The roundabouts keep traffic moving because the
typical speed to enter a roundabout is 10 to 15 mph.
Drivers still move, instead of sitting at a stop
sign or traffic signal.
Single-lane roundabouts can handle up to 18,000
vehicles daily, according to Bill Baranowski, a
traffic engineer in suburban Salt Lake City, who
said he has helped design 88 roundabouts in a dozen