50 firefighters dispatched to fire at water treatment plant on Montreal's South Shore

The fire caused major damage to administrative offices at a waste water treatment facility in Mont-Saint-Hilaire. Firefighters got the fire under control at around 5 a.m.

Fire caused major damage to administrative offices at facility in Mont-Saint-Hilaire

Firefighters got the fire under control at around 5 a.m. (Charles Contant/Radio-Canada)

Around 50 firefighters were dispatched to a major fire at a water treatment facility on Montreal's South Shore this morning.

The fire broke out just after 2 a.m. at the Régie d'assainissement des eaux usées de la Vallée du Richelieu in Mont-Saint-Hilaire, about 40 kilometres from Montreal.

Firefighters got the fire under control at around 5 a.m. after they had to cut the power to the facility.

The facility treats waste water from the towns of Mont-Saint-Hilaire, Beloeil, Otterburn Park and McMasterville.

Cause remains unknown

Jean Clément, director of the Mont-Saint-Hilaire fire department, said the fire appears to have started in a laboratory, but the exact cause remains unknown.

When the first firefighters arrived on the scene, they saw flames coming out of the windows at the front of the building, near the administrative offices, Clément said.

"The factory itself wasn't touched," he said.

Three firefighters suffered minor injuries.

About 50 firefighters from the towns of Mont-Saint-Hilaire, Beloeil, McMasterville, Sainte-Julie, Chambly and Saint-Basile-le-Grand responded to the fire. (Charles Contant/Radio-Canada)

Jacques Drouin, an administrator at the facility, told CBC News untreated water started flowing into the river around 2 a.m., while the facility was without power.

However, that's not uncommon, he said because it happens every time the power goes out.

Drouin said he expected the facility to be fully operational again by the end of the day.

"The system will work, but the office won't be available," he said.

With files from CBC Montreal's Lauren McCallum and Radio-Canada