The Canadian province of British Columbia is facing more heavy rains as it tries to recover from massive floods and mudslides, Public Safety Minister Mike Farnworth told reporters on Tuesday.

Farnworth said crews were working to shore up dikes and dams, adding some roads would be closed protectively.

Flooding earlier this month in Canada's westernmost province triggered landslides that killed four people, cut off rail access to Vancouver, Canada's largest port, and caused billions of dollars of damage.

"In some areas ... this could be the most intense storm yet," Farnworth said. "The cumulative effect of this succession of storms will be - and continues to be - a major challenge."

Officials said parts of the province could expect up to 4.7 inches (12 cm) of rain in less than 36 hours starting later on Wednesday.

The province on Monday extended a state of emergency through Dec. 14. That limits vehicles deemed "non-essential" by the government to 7.9 gallons (30 litres) of fuel.