Construction on a $77 million underpass project in Winnipeg's Transcona neighbourhood got underway Sunday, as the city shut down a section of Plessis Road for a year and a half.

Plessis Road between Dugald Road and Kernaghan Avenue will be closed to vehicles and pedestrians until the end of 2014.

The city aims to ease severe traffic congestion in the area by lowering Plessis Road and moving the CN Rail Line that crosses it just north of Dugald Road onto twin rail bridges.

Crews will also widen Plessis Road into four lanes, build a bicycle and pedestrian path and lower Dugald Road to accommodate the underpass.

Area residents who have long lobbied for the underpass say several trains block the busy street every day, which causes long commute times.

There are concerns about the length of time that Plessis Road will be closed, but the city said building a temporary bypass would have added up to $10 million to the cost of the project and extended the completion date by 18 months.

Construction needs to be finished by March 2015 for the project to qualify for $25 million in federal funding.

The city is encouraging drivers to use Regent Avenue West, Dugald Road, Ravenhurst Street and Lagimodiere Boulevard as alternate routes.

It said temporary traffic calming measures will also be put in place on Bournais Drive before school starts in the fall.

Two transit routes will be detoured.