Traffic will flow through the Waverley Street underpass a year earlier than expected, as the City of Winnipeg announced Tuesday the underpass will officially open this month.

The project, which was approved by city council in early 2016, was originally slated to cost $155 million and be finished by August 2020. It will now open on Aug. 19 of this year, the city says.

"This has been a long time coming," Mayor Brian Bowman said at a ribbon-cutting ceremony on Tuesday. Manitoba Premier Brian Pallister and Municipal Relations Minister Jeff Wharton, as well as federal Liberal MPs Jim Carr and Terry Duguid, also attended the ceremony.

The underpass project also included the rehabilitation of Waverley Street and the widening of Taylor Avenue to four lanes between Waverley and Lindsay Street. That work is expected to be completed in the fall, followed by art installations and landscaping work planned to finish in spring 2020.

The intersection sees upwards of 40,000 vehicles pass through every day, Bowman said.

Once the underpass opens, city crews will remove the detour road and reconstruct a portion of the Taylor Avenue intersection, the city said in a news release.

Bowman says an estimated 40,000 vehicles pass through the intersection every day. (Jeff Stapleton/CBC)

"Once fully constructed later this fall, the project will improve traffic safety, mobility and capacity, as well as enhance pedestrian and cycling opportunities," the city said in the release.

Multiple city, federal and provincial governments, under different political parties, have had a hand in guiding the project to completion, Bowman said, adding any one of those governments could have derailed it.

"It shows that that collaborative spirit has been there with all involved, which is something that will benefit motorists and those using the active transportation amenities," he said.

The project also came in under budget. It ultimately cost $98 million, the city's public service told councillors in April.

City council has already voted to return millions of dollars to the provincial and federal governments after it was determined the project would come in under budget.

"It's a good example of what happens when governments work together effectively, ahead of time, under budget," said Pallister, whose Progressive Conservative Party is seeking re-election on Sept. 10.

The underpass project involved moving a busy rail line — which sees between 35 and 40 trains pass by every day — to a bridge over Waverley Street.