Large sinkhole caused by groundwater leak in Montreal’s NDG, water cut to surrounding homes
Posted May 6, 2025 2:11 pm.
Last Updated May 7, 2025 4:14 pm.
Large pieces of asphalt fell onto water pipes in Montreal’s Côte-des-Neiges—Notre-Dame-de-Grâce borough due to a car-sized sinkhole that first appeared on Sunday night.
on Wednesday, Etienne Brunet, a spokesperson for the borough, said the hole at the intersection of Mariette and Somerled Avenues was due to a groundwater leak that was caused by an 8-inch pipe.
He added that it is now undergoing work, resulting with water being cutoff to immediate neighbours in the area — about six homes. The borough is hopeful that the water will be restored by tonight.
“The work is underway, so we excavated this morning,” he told CityNews. “So we enlarged the hole to be able to better make the repair.”
“We’re making a repair on the 8-inch secondary line.”
As of Wednesday, the main line is now fine — but they’re inspecting the sewers with cameras.
“There’s still too much debris inside the sewer,” said Brunet.
Before closing the hole, they need to do their checks properly, he explained.
Minimize the impact on residents
On Tuesday, Brunet explained that to clear around the primary 30-inch pipe they would be going “very slowly” with their mechanical equipment not to damage it more than what might already be broken.
“We’ve confirmed that an 8-inch secondary pipe is indeed damaged and broken,” he had told CityNews. “So we’re going to replace part of it right away.”
The borough had managed to avoid water cuts for residents then, but Brunet said that the area might see slightly lower water pressure.
“We’re taking a little more time to work because we aim to minimize the impact for the residents of the area,” he explained.
In addition to the pipes, part of the sewer has to be replaced because it’s sagging.
“That adds even more time,” said Brunet.
“When we’ve finished the entire investigation, of the intersection of all our underground infrastructure,” explained Brunet. “We’ll be able to make a game plan to say roughly how long it’s going to take (to be repaired).”
