Lake Elmo is joining the growing list of Twin Cities suburbs that are coming around to roundabouts.

Construction is scheduled to begin in mid-July on the circular junction where Hwy. 5 (Stillwater Boulevard N.) and County Hwy. 6 (Jamaca Avenue N.) meet, with the project expected to be complete by October.

The Washington County Board, in a 5-0 vote this week, signed off on the project, and the city is expected to follow suit.

Bids for the project, estimated to cost $1.6 million and overseen by the Minnesota Department of Transportation, will be opened on Friday. Nearly all costs will be funded by federal ($900,000) and MnDOT ($692,000) money that already has been earmarked for the project. That will leave the county's share at $24,000 and the city's portion at $15,500.

Improving safety is the primary driver of the project, said Wayne Sandberg, Washington County's deputy director of public works.

"We're concerned with crashes -- we have many crashes there," he said. "It's also difficult to make a left turn."

"I drive this intersection every day, and it is a dangerous intersection," added County Board Chairman Bill Pulkrabek. "... So I'm glad we're doing it."

Roundabouts have been proven to reduce both the number and severity of traffic accidents at intersections, said MnDOT spokeswoman Mary McFarland Brooks. There are 39 percent fewer crashes at roundabouts compared to four-way intersections, and 89 percent fewer fatalities because of slower speeds and reduced crash impacts, she said. They are also less expensive to maintain than intersections with signals.

The Lake Elmo project also fits well with the rural landscape, she added, and will help calm speeds of vehicles coming from Interstate 694. "We have a lot of problems with speed in that area," she said.

From I-694 east to Jamaca Avenue, Hwy. 5 is four lanes wide, then narrows to two lanes. The roundabout also will offer a smoother and safer transition to the narrower roadway by slowing traffic as vehicles enter the roundabout, Sandberg said.

The design also includes right-turn bypasses -- traffic heading south and turning west, or going north and turning east -- will not go through the roundabout.

Both Sandberg and McFarland Brooks said local residents have supported the project at public meetings where it was explained.

There are 14 other roundabouts in Washington County, according to MnDOT. Eight are in Woodbury, three in Lakeland/Lakeland Shores, two in Cottage Grove and one in Stillwater. There are 86 roundabouts either built or under construction in Minnesota, and the number is certain to grow -- nearly 100 more are in various stages of planning.

Jim Anderson • 612-673-7199