Major water main break in Montreal telling of ageing infrastructure, says expert

Drone footage shows flooded Montreal streets Drone footage of flooded streets in downtown Montreal after a massive water main break.

The water main break in downtown Montreal on Friday is the second major piping issue on the island in a little over a month and could be telling of the city's ageing water infrastructure, according to a civil engineer.

"Just a month ago, there was the break next to the McGill Health Centre, which led to it being closed down for a few hours," said Dr. Rebecca Dziedzic, assistant professor at Concordia University in building, civil and environmental engineering. "It's a reminder that these things can happen, and they really affect the safety of the people around."

Dziedzic estimated that most of the water infrastructure in Montreal could be around 50 to 60 years old, and "this is when we start to see more breaks," she said.

The pipe involved in Friday's water main break was installed in 1985, officials said at a news conference.

In the last two decades, Dziedzic said more attention has been brought to the age of water piping systems in Canada. She noted that the Canadian Infrastructure Report Card collects data every few years on the state of infrastructure in Canada, including water mains and sewers.

The latest report, produced in 2019, showed that 30 per cent of water infrastructure is in fair, poor or very poor condition.

"At the same time, the cities are getting more aware and they are improving," said Dziedzic. "So, actually, we have been seeing in some cities across Canada the number of breaks going down. If proper maintenance is done—as long as we're doing the preventative work—they can definitely go down."

Dziedzic said that right now is the best time for cities to do more inspections and assessments of their water piping systems.

"For example, there are devices that use sound or electromagnetic inspection to get an idea of what the condition is, if there's any little cracks, corrosion, any failures that could lead to a break," she said, adding that types of soil, of operation, the pressure variation all come into play as well.

Steps to reparation

The city is currently working to shut the water supply in the area.

Once the water has been drained, then the next step will be to identify what caused the break, as well as the size of the damage.

"They'll see what's the extent of the damage, and that'll depend on if that material is closely available, or they're going to have to source it—that might take longer, as was the case in in Calgary a couple months ago," said Dziedzic.

Only then will it be clear how much longer repairs will take, according to her.

Immense pressure

The pipe that broke was more than two metres in diameter and carried drinking water.

"Beyond the size of the pipe, the whole water system is pressurized, and so it's a huge amount of water and speed," said Dziedzic. "When that breaks, it's all coming out like a like a geyser."

Dziedzic noted how often the size and magnitude of the water infrastructure are overlooked.

"It's good for people to remember that we have this amazing infrastructure underground," she said. "It's moving huge amounts of water that we rarely think about. But, in general, it's delivering a great service. Everyone has clean water, it's healthy, it's safe," she said.

"But certain times it can fail, and the city has the has the responsibility," she added. "Us, as residents, we can call for better inspection assessment and make sure—especially in these areas that are critical—that our infrastructure is in great condition."