Investigation into water main break continues

Multiple roads in and around the Jacques Cartier Bridge are closed after a massive water main break in Montreal's Ville-Marie borough. (Daniel J. Rowe/CTV News)

Montreal officials are focusing on preventative measures after last Friday's major water main break, which occured despite previous warnings that the pipe was vulnerable. 

During a techinical briefing on Tuesday, the city said it's still not clear what caused the break near the Jacques Cartier Bridge. 

An inspection in 2018 showed corrosion and city officials have said they were made aware that the massive water main was vulnerable.

Another inspection had been planned in the upcoming months, according to the city.

"But there is no such thing as zero risk. And here we have an example of accelerated deterioration," said Chantal Morissette, the director of water services, during the briefing.

"We're going to dig deeper. We're going to see if there are elements that we might consider, but here we're really looking at a preventive strategy."

Following Friday's water main break, the city said they acted according to their intervention plan.

The specific pipe that bust did not have an outside coating to protect it from corrosion. In fact, there are 150 KM of this same model across the island, 110 KM of which lack outside coating.

The city said it started installing outdoor coating over the years, and these pipes are regularly examined. On average, water mains are inspected every five to seven years depending on their condition.  

Officials also noted that, on average, two pipes break every year.

Moreover, the city is conducting further analysis on the segment of the pipe that broke to understand why it burst and to identify any information that could help prevent future incidents like this one, as well as to determine the cause of the accelerated degradation.