Four missing as Canada floods cause 'unimaginable' damage

Two children unaccounted for after car in which they were travelling overcome by floodwater

Buildings almost submerged in floodwater after torrential rain in Halifax. AP

Four people, including two children, are missing as severe flooding hit Canada's Nova Scotia province, authorities said on Saturday evening.

Royal Canadian Mounted Police described a harrowing situation in which three people escaped from a car submerged in water but were unable to rescue two children inside.

In a separate incident in the eastern province, a youth and a man were reported missing in similar circumstances, police said.

Heavy rain since Friday in Nova Scotia has cut off roads and flooded homes.

Premier Tim Houston told a news briefing that the province had received some 25cm of rain – the equivalent of three months' rainfall – in less than 24 hours.

“We have a scary, significant situation here,” he said. "The list of infrastructure damage to bridges, roads and other buildings is long … and it will continue to grow."

He estimated it would take several days for the water to recede and described damage to peoples’ homes as “pretty unimaginable”.

Halifax mayor Mike Savage warned flooding could continue into Sunday and there was no room for complacency.

“People should not assume that everything is over, this is a very dynamic situation,” he said. Around 80,000 people were left without electricity due to the flooding.

People in the Windsor region received evacuation orders in the middle of the night amid fears flooding would cause the breach of a nearby dam.

But relief valves were opened early Saturday to reduce pressure and the situation is now under control, said Windsor Mayor Abraham Zebian.

News footage and images on social media showed significant flooding and many cars abandoned in the water.

Environment Canada's weather service said heavy rain was expected into the evening in the eastern part of the province.