Communities evacuated, highways washed away as relentless rain pounds B.C.

Heavy rain battered southern British Columbia on Monday, forcing the evacuation of an entire city, washing out major highways and leaving many communities cut off from the rest of the province.

Parts of the province have seen as much as 252 millimetres of rain in just two days, and rainfall, snowfall, winter storm and wind warnings remain in effect across most of southern B.C.

Environment Canada is forecasting winds gusting up to 90 kilometres per hour on Monday evening in some regions.

In a news conference Monday afternoon, Public Safety Minister Mike Farnworth said conditions are still in flux. Mudslides and debris flows have washed out portions of Highway 1 and the Coquihalla Highway, and flooding has forced people from their homes in several communities.

"People in Merritt, Princeton and areas along Highway 7 and 99 and the Coquihalla are seeing the worst of it," he said.

"I would like to thank everyone who is affected for your patience, strength and for doing everything you can to stay safe. As I said this morning, the situation is dynamic and further rains, high winds and possible snow in areas are compounding the situation."

Despite the chaos in many regions, there have been no confirmed deaths so far.

Residents of Merritt, some 180 kilometres northeast of Vancouver, were ordered to evacuate at about 10 a.m. PT on Monday. City officials said the municipal wastewater treatment plant in the community had failed. Residents were asked not to use water in their homes, including flushing toilets and running taps.

An evacuation order was also issued for the nearby Nooaitch Indian Band. 

The city has asked all gas stations to remain open for residents leaving the city. Reception centres for evacuees are open in Kelowna and Kamloops. 

Meanwhile, rescue operations were underway in multiple locations after mudslides trapped drivers in their vehicles on B.C. highways. That includes an area south of Lillooet where Farnworth said about 50 vehicles had been stranded.

On Monday afternoon, helicopter rescues were underway along Highway 7 between the communities of Hope and Agassiz, where as many as 275 people, among them 50 children, had been trapped in their vehicles since Sunday.

Canadian Forces Cormorant helicopters lifted hundreds of people to safety, transporting evacuees from the slide area to a reception centre in Agassiz. 

Camp Hope, a camping and conference centre located along Highway 7, is offering refuge for stranded travellers in the area.