A stretch of Portage Avenue near Donald Street was down to one lane after the road buckled late Wednesday afternoon.
The city confirmed Thursday heat is what caused the pavement to shift.
Repairs to the major thoroughfare will take a few days. Crews need to excavate, replace the base and joints and pour concrete which will need to cure for at least 24 hours before the road can reopen.
WATCH: Traffic delays will continue for a few days as construction crews work to fix Portage Avenue
It’s the second roadway to shift in as many days in Winnipeg. A section of Scurfield Boulevard buckled Tuesday, where again the city said heat was also to blame.
Dr. Ahmed Shalaby with the University of Manitoba said buckling is more common on sidewalks but it’s expected more roads could shift in the future because of climate change.
“With more dry and hot weather predicted due to climate change, it is expected that these failures could become more frequent,” Shalaby said.
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So what causes a road to buckle?
“Over an extended period of one to two weeks in the summer, sustained heat, exposure to sunshine and dry weather could elevate the temperature of the massive 10 inch thick pavement causing it to expand,” Shalaby explained.
“As the road slabs expand during a heat wave, they close all the gaps provided by the joints and there could be a build up of thermal stresses. To relieve excessive thermal stresses one of two types of failure may occur: buckling of the road, or crushing of a pavement slab to small pieces. In either case, the failure acts as a fuse that breaks to relieve excessive stress from a particular section of road.”