City crews launched a USD 2.6 million project on Tuesday morning on a critical road in Missoula -- South Third Street West, from Russell to just west of Schilling.

Local businesses are open. Westbound traffic will be rerouted up Catlin to South Fifth West, then back to Schilling. Eastbound traffic will move up Schilling to South Fifth and then to the light, at Fifth and Russell.

The Third Street project will create a new and safer roadway on the heavily-traveled corridor.

The detours and road closures came as a surprise for a lot of drivers coming off a Memorial Day weekend.

Missoula City Engineer Kevin Slovarp said that "We currently don't have room for all modes of transportation."

Slovarp explains that the city will be making improvements like adding a center turn lane, 2 driving lanes, plus bike lanes and sidewalks on both sides. It's designed to give pedestrians, bikes and cars a little separation.

Slovarp said that "Provide a safe and efficient lane or sidewalk for those folks to utilize."

The construction will continue into September, leaving some drivers less than pleased.

One Missoula resident said that"That's way too long. Road construction like this, this isn't even a mile stretch long that they're doing. It should be done in weeks."

"It's a pain in the butt!" said resident Sean O'Brien.

"I sometimes question why they do things the time that they do. It seems extremely disruptive to the traffic pattern," said resident Angela Hardy.

Bystanders tell NBC Montana they've seen drivers speeding through the construction and our reporter witnessed a fender bender. Slovarp says drivers should expect delays and slow down.

Resident Ann Watson said that "Think about the improvements that it's going to make in the long run. It's really worth the inconvenience in the short term."

Resident Linda Lee said that "I really haven't even noticed. It hasn't really bothered me."

Resident Jason Watson said that "You've just got to grin and bear it and just make the best of it."