Herald Journal, April 26, 2004
‘Roundabouts’ planned for Highway 7 in 2006
By Lynda Jensen
A touch of Europe will likely be seen on Highway 7 in Carver County when the state constructs two “roundabouts” there in 2006.
This is part of rebuilding the stretch of Highway 7 from Silver Lake to St. Bonifacius.
Roundabouts, sometimes called traffic circles, have been used with great effectiveness in Europe for several years, according to Kelly Brunkhorst of the Minnesota Department of Transportation (MnDOT).
They entail a circular traffic pattern that causes traffic to go in a semi circle, without stopping (see graphic).
They are yet rarely seen in Minnesota, with one being found near Medina; although they exist in other states and Canada.
Traffic studies in the United tates and other countries give very positive reports regarding roundabouts.
One such study found an average decrease of 90 percent in accidents involving serious injuries or fatalities by the Insurance Institute for Highway Safety.
“Modern roundabouts have great overall operational efficiency than all other forms of traffic control,” reported a study by Kansas State University.
The Canadian Society of Civil Engineers also gave its stamp of approval on roundabouts.
The roundabouts will be placed at the intersections of Highway 7 and Highway 25 between Watertown and Mayer, and at Carver Co. Rd. 10 between Watertown and Waconia.
In addition to the roundabouts, three passing lanes will be installed as well as a center left-turn lane north of Lester Prairie on McLeod Co. Rd. 9 along Highway 7.
The passing lanes will be located:
• east of Silver Lake near the intersection with McLeod Co. Rd. 15.
• near the Carver Co. Rd. 21 intersection.
• between Highway 25 and Carver Co. Rd. 10.
A solution for severe right-angle crashes
The traffic control measures are expected to address severe, right-angle crashes at each of the intersections listed.
This includes three fatal crashes at the Co. Rd. 10 intersection in the past 10 years.
Both intersections at Highway 25 and Co. Rd. 10 along Highway 7 have experienced an average of five crashes per year, with about half of them involving people injured or killed, according to Paul Kachelmyer of MnDOT.
Nearly all of the crashes involved right angle or left-turning crashes.
Incidentally, these intersections also meet certain warrants for traffic signal light justification, he said.
Roundabouts are ideal for high speed, rural two-lane highways such as Highway 7, Kachelmyer said.
A highway similar to Highway 7 in Maryland was given a roundabout known as the “Leeds Roundabout” with great success, Kachelmyer said.
“In the six years before the reconstruction of that intersection,there had been 42 people injured and one person killed at that one site,” Kachelmyer said. “In the six years after the intersection’s reconstruction to a roundabout, there was only one person injured.”
In fact, Maryland loves roundabouts so much that it reconstructed an additional 38 roundabouts by 2003.
Kansas is also building roundabouts at a fast pace, since they appear to solve so many traffic issues and require little maintenance compared to traffic lights.
If everything goes according to plan, traffic will be detoured through Lester Prairie during the summer of 2006 while the construction takes place.
The detour is planned to divert traffic south of Silver Lake on McLeod Co. Rd. 2, then east on Co. Rd. 22 through Lester Prairie, and on Carver Co. Rd. 30 through New Germany and Mayer, before being directed back to Highway 7.
Bids will be awarded in November of 2005, with work starting May 1, 2006.
Highway 7 from Silver Lake to Carver Co. Rd. 10 will be milled down by two inches and a new four-inch overlay will be put into place.
The total cost to the state is estimated $6.2 million.