MONTREAL – Service resumed on the Montreal Metro's orange line around 1 p.m. Thursday, several hours after a large section of it was closed due to a major water main break at the Square Victoria-OACI station.

Montreal Mayor Valérie Plante says workers located the source of a major leak that forced a partial closure of the line, between the Lionel-Groulx and Berri-UQAM stations.

 “A lot of water is coming into the station, so what we are trying to do right now is make sure the water doesn’t break our electric system,” Luc Tremblay, Director General of the STM told CTV News earlier on Thursday.

“It’s a very bad time to have a water leak because it’s rush hour, so it’s a very big deal.”

The Montreal fire department says it received a call at 5:45 a.m. about water leaking into a building on Viger Street and Beaver Hall Hill.

Water infiltration n Montreal Metro

The break was capped and after an extensive clean-up of the Square-Victoria-OACI station, it reopened just after 3 p.m.

The Montreal fire department and public works were also onsite.

The Ministry of Transport is working to evaluate any potential impacts on the Viger Tunnel. During the day, the STM added buses to its service to help people get around.