West Island residents are dealing with flooding as water levels on the back river rose about 30 cm overnight.

The Riviere des Prairies rose rapidly around midnight, flooding Ile-Mercier and parts of Ile-Bizard and Pierrefonds.

"In two hours the water came up," said one woman who got home at 11 p.m. Tuesday when streets were still dry.

"It was full of water. We tried to save everything, I tried to save my car, my dad is trying to save his truck. The water is all over the place. My car stopped and the fireman pushed me down the street. It's full of water," she said.

"The house is still okay but the water is coming to the door so I hope it won't get worse."

In Pierrefonds streets north of Gouin Blvd. between Des Rivieres St., and Bouchard St. were suddenly inundated. The water also rose rapidly on Ile Mercier, a small island connected to Ile Bizard by a low-lying bridge.

Several streets in the area are closed.

The city is asking residents that are unsure of road closures or have questions about the situation to call 311.

Sandbags stored in a borough warehouse were destroyed earlier this week because they were taking up too much space.

Borough Mayor Jim Beis now recognizes it was a poor decision and said the borough is doing all it can.

“The priority is to make sure the citizens are safe, and then I'm sure we’ll have plenty of time to analyze the situation to see if there was something City of Montreal could have – was it done or not,” he said. 

Firefighters rushed to the areas affected to help out residents. In some cases they installed pumps to help empty basements that were filling with water. In others they evacuated homes and rescued stranded people.

For those who are staying in their homes, the Montreal fire department has a reminder:

“If you are using a generator, don't use it inside your house. There is carbon monoxide produced by these generators,” said fire department spokesperson Martin Guilbault.

One man took to a rowboat to check on the neighbourhood during the day, and told CTV how he rushed to move things to safety overnight.

"A foot of water inside the garage was flooded. I moved two cars," he said.

Another woman said there was no water at all on her street at midnight, but one hour later the water was one metre high.

About 30 houses on the western tip of the island are coping with rising water.

At midday Civil Security for Montreal issued an alert for all citizens near Lake of Two Mountains and Lake St. Louis to acquire pumps and to get items off their basement floors.

Anse à l'Orme Rd. between Senneville Rd. and north of Timberlea Trail is closed in both directions until further notice.

There has also been significant flooding this week in Rigaud, and in central parts of the province.

The few dozen residents of Ile-Mercier just off Ile-Bizard have been on alert for several weeks after their only roadway off-island was partially submerged in mid-April.

With a new surge of water this week, Ile-Bizard called for a voluntary evacuation of the 30 or so homes on Ile-Mercier, though only 5 to 10 per cent of its 100 inhabitants have left, the rest choosing to stay and tend to their homes.

"Generally people don't want to leave. They just want to stay in their house so they can supervise their sump pumps they want to protect their house," said Ile-Bizard Mayor Normand Marinacci, who said spring flooding hasn't been this bad since 1998.

"The biggest worry is it keep coming up and up and there’s always a problem with electricity. That’s my main fear. That’s where the fire department might have to make a decision that is drastic and force people to get out, but for the moment everything is under control," he said.

On the south side of the island, no homes have been flooded in Pointe Claire, although the winds have help push water from Lake St. Louis further inland. 

The city has closed Cartier Ave. south of Lakeshore Rd., and closed Bourgeau Park as a precaution.

The Pointe Claire Yacht Club is closed because the water level is higher than the boat ramp. People at the club said they have never seen, nor can they remember, the water level on the lake ever being so high.

Laval has also issued a warning to shoreline residents, who are encouraged to call 311 to request delivery of a sandbag pallet, or to go to one of the bulk sandbag lots to pick some up.

Water levels are expected to continue to rise this week and next due to the heavy rain that fell on Sunday and Monday, and with the rain expected later this week.