Rocker roundabout

Work is underway on a roundabout at this spot pictured Thursday on the north side of the Rocker interchange of Interstate 15-90 about 3 miles west of Butte. It will be the first roundabout in the Butte-Silver Bow area and should be completed this year, transportation officials say.

Work on the first roundabout in the Butte area is underway at the Rocker interchange of Interstate 15-90, and most of the $6-million project should be completed by November.

Even though many people have negative takes and apprehensions about roundabouts at first, most come to like them, Bill Fogarty, a district construction supervisor for the Montana Department of Transportation (MDT), said Thursday.

“As soon as they drive them and they see how they flow and (realize) you don’t have to stop, they’re immediate fans,” Fogarty said.

When the project is completed, there will be a six-legged, single-lane roundabout on the north side of the Exit 122 interchange near the Flying J truck stop. The ramps on the south side near the Town Pump Travel Plaza will be widened and improved, Fogarty said.

The roundabout will have six entry or exit points, including on and off ramps to west-bound Interstate 15-90, both directions of Browns Gulch Road, the access point to the Flying J, and the lane that goes under the interstate toward the south side truck plaza.

MDT officials say the improvements were selected to increase ease of use and traffic flow “in an area with high volumes of commercial and private vehicle traffic.” The changes will meet updated state and federal standards of safety, cost-effectiveness, and efficiency.

The project, as most highway endeavors are, has been in the works for several years. There was an open house at the Rocker Volunteer Fire Department in December 2015 to discuss the plans, including the north-side roundabout.

Work began this week on the first phase of the project, which is creating detours on the ramps to bypass the primary construction area. Motorists will still use the same ramps, and there will still be easy access to the truck plazas, Fogarty said.

Work on the roundabout itself should start by mid-May, he said, and most of the entire project should be completed by November or December. A few things might fall into 2020, but the roundabout should be in action.

The roundabout will be a single lane 17 feet wide, but the interior will have colored and patterned concrete called a “truck apron” to accommodate semis and other vehicles pulling separate trailers. It’s essentially an extended area for the trailers.

Roundabouts might seem complicated, but a few basics gets motorists through them. Slow down, look left, and turn right, and once you're in one, you have the right of way. Use your right turn signal to exit.

There are several in Montana, including in Billings, Bozeman, and Missoula. There are at least 13 in Billings alone, and there’s one going in this year at York Road and Lake Helena Drive in Helena. But Fogarty said this will be the first in Butte and nearby areas in southwest Montana.

They are quite popular in some American cities, perhaps none more so than Carmel, Indiana, an affluent suburb of Indianapolis that’s home to about 93,000 people.

The city, on its website, says it has become “internationally known for its roundabout network” that it began building in the late 1990s. It now has more than 100 roundabouts, “more than any other city in the United States,” it says.

The city says they are safer, compatible with the environment, aesthetically pleasing, and make it easier for pedestrians and bicyclists to navigate, too.

“In Carmel, where roundabouts have replaced signals or stop signs at intersections, the number of injury accidents has been reduced by about 80 percent and the number of accidents overall by about 40 percent,” the city’s website says.

Fogarty said in his experience with them, very young motorists and elderly drivers are most apprehensive about them. Those in the middle take to them quicker, he said.

Subscribe to Daily Headlines

* I understand and agree that registration on or use of this site constitutes agreement to its user agreement and privacy policy.

Government and politics reporter

Mike Smith is a reporter at the Montana Standard with an emphasis on government and politics.

Load comments