by T.W. Budig
ECM Capitol Reporter
The fastest and safest way to drive between two points may be through a circle.
Actually, roundabouts are not like traffic circles, in use for a century.
With their strategic pedestrian crossings, one-way traffic flow, U-turn friendliness and slowing effect on speed, roundabouts can move traffic smoothly, safely and at reasonable costs, highway experts say.
In Minnesota, about 119 roundabouts have been built statewide. The Minnesota Department of Transportation has been completing up to 10 roundabouts a year over the past few years, MnDOT engineer Ken Johnson said.
Within the metro, Dakota, Hennepin and Washington counties boast the most roundabouts. But they’re also found in Chisago, Mille Lacs and in other Greater Minnesota counties.
About 29 roundabouts are on the drawing boards across the state.
“The roundabouts that have been installed in Edina are working very well,” Edina Director of Engineering Wayne Houle said in an email.
As anyone who has gulped while watching a car rocket through a red light can attest, intersections can be hairy. About a third of all intersection fatalities occur at signalized intersections in the United States, according to the Federal Highway Administration. About 700 Americans are killed every year in red-light running crashes, it notes.
Roundabouts offer an alternative. Studies reveal sharp decreases in accident rates, severity of injury and number of fatalities through the use of roundabouts.
Roundabouts play a role in Minnesota’s declining highway death rate, Johnson indicated.
A recent study in Wisconsin, which has more than 200 roundabouts and is aggressively building more, conducted by the Wisconsin Department of Transportation and University of Wisconsin researchers focusing on 24 roundabouts in the Badger State, showed the number of fatal and injury crashes dropping by about half.
A 9 percent accident rate decrease across all 24 roundabouts was achieved.
Roundabouts are proving themselves in Minnesota, too.
A study by MnDOT of roundabouts on Highway 5 in Washington County, Highway 7 in Carver County and Highway 13 in Scott County showed an overall 41 percent decline in crashes, with a 70 percent decline in injuries, and no fatalities.
This is compared to two fatalities prior the construction of the roundabouts.
Indeed, the Highway 13 and County Road 2 roundabout in Scott County has been profiled by the Federal Highway Administration as a textbook example of where a roundabout quieted a deadly intersection after steps like larger stop signs, striping and flashing lights fell short.
A Scott County official called the roundabout wildly successful.
While studies show accident rates on multiple-lane roundabouts as similar to other intersections, crashes tend to be less severe, Johnson said. That’s because, though rear-end collisions or sideswiping occurs, chances for violent, T-bone style crashes are greatly reduced.
Cost of constructing roundabouts is comparable to constructing signalized intersections, between $1 million to $1.5 million, Johnson said.
Mini-roundabouts, or roundabouts where the island in the center is simply a round hump, can cost much less.
The islands are not designed for pedestrians; that’s exactly where traffic engineers do not want them to congregate, Johnson said. The islands are designed to help guide traffic through the roundabout; in some cases, a raised inner apron around the island is constructed for truck use.
County engineers look at roundabouts as another transportation tool.
“I certainly expect the number (of roundabouts) to grow,” Washington County engineer Joe Gustafson said.
Currently, a handful of roundabouts are proposed for various locations in Washington County. The county’s website offers “Roundabout U,” a page where the public can learn about navigating roundabouts.
The knowledge is increasingly useful. Dakota County recently opened a new roundabout on Dodd and Highview in Lakeville.
“There’s a little bit of a learning curve,” Johnson said about the public’s reaction.
Studies show that about two-thirds of the public have negative impressions of roundabouts prior to construction, he said. But within a few months of openings, the perception flips to largely positive, Johnson said.
“Some people love them. And they want them everywhere,” Anoka County highway engineer Doug Fischer said.
There are no roundabouts on state or county roads in Anoka County, he said. The county is considering two, single-lane roundabouts in future highway projects.
“We’re just sticking our toe in the water to see what it’s like,” Fischer said of public acceptance.
One group not overly fond of roundabouts are specialized truckers.
John Ehr, of Perkins Specialized Transportation of Northfield, described the chances of their trucks hauling their oversized loads successfully through roundabouts as “very problematic.” Trying to get around a roundabout usually means finding an alternative route, Ehr said.
Ehr credits Wisconsin officials as being more receptive to the needs of speciality truckers.
How many roundabouts will Minnesota ultimately have?
Johnson points to Australia, to the State of Victoria, similar in population and size to Minnesota. In 1972, there were three roundabouts in Victoria, he said. Today, there’s 5,000.
“To me, that’s kind of staggering,” Johnson said.
Nationally Minnesota is in the top 10 percent in terms of building roundabouts, Johnson said. But it doesn’t match the flurry to the east.
While MnDOT has been building up to 10 roundabouts a year, Wisconsin has been churning out 50 a year, Johnson said.
Gov. Mark Dayton drove on roundabouts in Massachusetts and is less than passionate about them.
“I can’t say I was fond of them,” Dayton said. “(But) I understand their (MnDOT’s) strategy, which is to maximize the efficiency of a substandard system,” he said.
The city of Brooklyn Park built the first roundabout on a state-aid roadway in Minnesota in 1995.
Tim Budig can be reached at firstname.lastname@example.org.