Story highlights Trans-Canada Highway bridge to close

River in Medicine Hat is predicted to peak Monday

About 10,000 people there have evacuated

Flooding has killed at least three people

As waters receded in some parts of southern Alberta, yet another city evacuated residents and lined up sandbags, waiting for a river to burst its banks.

The city of Medicine Hat cast a wary eye on the South Saskatchewan River, which authorities predict will reach its peak on Monday morning and flood at record levels. City Hall was lined with sandbags.

Officials told residents they should plan for the Trans-Canada Highway bridge to close Sunday night. The move will essentially split the city in half, allowing no public access between the northern and southern sections.

Nearly 10,000 people have been evacuated in Medicine Hat, and almost everyone has complied with evacuation orders, the city's mayor, Norm Boucher, said. City spokeswoman Brandy Calvert said officials expect the flood to eclipse one in 1995, the city's biggest on record.

So far, water treatment and power plants in Medicine Hat are protected. The drinking water is safe.

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"We don't want to anticipate the worst, but we're going to be prepared for the worst," Alberta Premier Alison Redford said. "We know that, from what we've seen everywhere else, that this is more exceptional than we've ever seen in Alberta before, so we're presuming that that's probably the circumstance that we're looking at (in Medicine Hat) as well."

The extensive flooding that has deluged towns and threatened southern Alberta communities has killed at least three people, officials said. The victims were all found in the Highwood River, about 40 miles south of Calgary.

In Calgary, water still covered the city days after the Bow and Elbow Rivers overflowed. Bruce Burrell, director of the Calgary Emergency Management Agency, said power could be out in the core of the city for days or weeks.

"The city of Calgary took a pretty hard hit, but we're a resilient city," Burrell said at a news conference Sunday. "We want to recover as quickly as possible, we want to get people into their homes and businesses as quickly as possible, we want to restore the city as quickly as possible."

The city was under a state of emergency late Saturday, but Mayor Naheed Nenshi said the flow of the water was slowing and some people could start returning home.