Roundabout construction begins at Orange, I-90 interchange

Work to ease a frustrating intersection just off the Interstate 90 interchange on Orange Street has begun with the construction of what’s billed to be Montana’s first five-legged roundabout. (Martin Kidston/Missoula Current)

By Martin Kidston/Missoula Current

Work to ease a frustrating intersection just off the Interstate 90 interchange on Orange Street has begun with the construction of what’s billed to be Montana’s first five-legged roundabout.

The $3.1 million project, awarded to Knife River Construction last summer, represents the first of three roundabouts planned along Missoula’s interstate corridor.

“The project should be completed by the end of June or early July at the latest,” said project manager Bob Vosen. “It’s a really aggressive schedule, but there’s incentives built in to ensure they get the work done on time.”

The roundabout will tie in a number of streets, including the westbound on- and off-ramps on I-90, as well as Orange Street and North Fifth Street West. It will also divert traffic through the intersection with a number of new arrangements.

Vosen said crews will work through April 15 on the roadside shoulder, shoring up a retaining wall and digging the retention ponds. During that time, traffic impacts will be light, though that will change as the work shifts to the roadway itself.

Vosen said a $12,600 daily incentive has been worked into the contract to ensure the work is done by the end of June.

“He gets charged for every day he overruns the project, but if they get done early, there’s an incentive,” Vosen said. “The entire project should be done by early July. We’ll also be updating the lights with LED luminaries.”

The Montana Department of Transpiration also plans to construct two roundabouts at the Van Buren interchange next year. That $7 million project will include something of a dog-bone design with a roundabout set at both the east- and west-bound exit ramps.

Shane Stack, the project engineer with MDT, said the agency looked at the interstate system through Missoula and found it suited for future growth. However, he said, the study found issues at both the Orange and Van Buren interchanges.

Contact reporter Martin Kidston at info@missoulacurrent.com