Four people remained missing on Sunday after floods swept through Nova Scotia and parts of the province recorded its heaviest rainfall since 1971, forcing hundreds to evacuate and damaging or destroying 25 bridges, the authorities said.
The heavy rains have subsided, and the flood water was gradually receding, said Jim Abraham, past president of the Canadian Meteorological and Oceanographic Society.
The two-day rainfall totals in Bedford, just outside of Halifax, reached about 250 millimeters, or nearly 10 inches, of rain. In Halifax, the rainfall was 100 to 150 millimeters, or nearly four to six inches, over the course of Friday and Saturday.
“This precipitation, peaking at 10 inches, is very rare,” Mr. Abraham said. “The last time in the Halifax area we had precipitation that high was in 1971 with Hurricane Beth.”
He pointed out that today’s population today is higher, with more infrastructure, “so the impact — I expect when added up — will be substantially worse than back in 1971.”
Six bridges were destroyed and 19 others were damaged, officials said.
Nova Scotia’s Department of Public Works is repairing damaged infrastructure as quickly as possible, Mark Peachey, the department’s chief engineer, said.
“People should be able to get where they need to go over the next couple of days,” he said. “Projects are being prioritized by need.”
As many as 600 people had to evacuate across the province, while many were stranded and some lost power, Tim Houston, the premier of Nova Scotia, said at a news conference Sunday afternoon.
Searches continued on Sunday for the four people who were reported missing early Saturday morning in West Hants, about 50 miles northwest of Halifax.
Two were children, between the ages of 2 and 12, who were traveling in a vehicle that became submerged, the Royal Canadian Mounted Police said. Three other people in the car with them were able to escape, the police said.
Separately, a teenager and another man were missing after a vehicle in which they were riding became submerged on a flooded road. Two others traveling with them were rescued, the police said.
Mr. Houston urged people not to look for those missing.
“To the families, you have an entire province praying for your loved ones’ safe return,” he said. “I know so many of you want to help. But again, given the treacherous conditions, the R.C.M.P. continues to ask people to stay away from the area so no one’s put at risk.”
An underwater recovery team on Saturday searched a flooded field and found an unoccupied pickup truck that the authorities believed was the vehicle that the children were in, the police said.
Industrial pumping equipment from civilian contractors were being used to lower the water level in the search area.
The flooding left residents in precarious situations.
Loushanna Carr, 33, of Ellerhouse, had to kayak from her home to get gas for her generator so she could keep her electricity running. Upon her return home, she felt her paddle hit something hard. She said it was a submerged car.
“The fire department came out and got into it,” Ms. Carr said. “Thank goodness no one was in it, and the woman that owned it was safe.”
A volunteer group, Halifax Search and Rescue, was called about 7:30 p.m. on Friday and worked until 3:30 a.m. on Saturday and then promptly started again after only a two-hour break, Paul Service, a group spokesman, said.
Members of the group searched for stranded motorists, used boats to help people leave their apartments and rescued about 20 people from the Bedford Place Mall in Bedford, he said.