Imagine... coming off I-90 at the Orange Street exit and encountering a giant five-spoke roundabout instead of the traffic pattern you've been used to for so many years.

That's the plan from the Montana Department of Transportation as the transformation is underway at the Orange Street interchange. Project Director with the Knife River construction company, Mike Eichner, said most of the initial construction will be done in the overnight hours, as to not delay daytime traffic.

"This week, starting Wednesday night at 9::00 p.m. we'll be tying into the existing storm water system on Orange Street, in between Third and the eastbound off-ramp,"  Eichner said. "We're going to have to get out into Orange Street. We'll have flaggers directing traffic that night, just for a few hours. Then, on Thursday night starting at 9:00 p.m. we're going to close the eastbound off-ramp at Orange Street and do a storm water pipe crossing, and that should take about four hours, hopefully reopening at about 1:00 a.m."

Eichner said the eastbound on and off-ramps will he the most affected by the construction, while the westbound on and off-ramps should be unaffected, except for coming into Missoula.

"The roundabout phase is about a month and a half, so we are slated to be done with that about the end of May," he said. "The rest of it around Third and the sidewalk and curbs along the Providence Center will all be done by the end of June."

Drivers are encouraged to slow down and watch for workers during construction.