Devastating flooding forces tens of thousands from their homes in southern Alberta

Three people are dead, another is missing, and tens of thousands have been forced from their homes in Calgary and throughout the rest of southern Alberta over the past 36 hours, with more being evacuated from Medicine Hat, as swollen streams and rivers overflowed their banks, some with so little warning that residents had no choice to flee to the roof of their house to await rescue.

Twenty-six communities along the Bow and Elbow Rivers in the city of Calgary were evacuated on Thursday, displacing an estimated 75,000 people from their homes in anticipation of flooding in the city, and more evacuations are taking place today as the entire downtown area suffers power failures.

[ Related: Severe flooding prompts evacuations in southern Alberta ]

Residents woke this morning to find several areas of the city under water as it is believed that both rivers crested either overnight or this morning, and more rain is on the way.

Mandatory evacuation orders were given for Beltline, Bonnybrook, Bowness, Bridgeland Industrial Area, Chinatown/Eau Claire, Cliff Bungalow, Deer Run, Discovery Ridge, Douglasdale, Downtown/East Village, Elbow Park, Erlton, Inglewood, Hillhurst, Mission, Montgomery, Quarry Park, Rideau, Riverbend, Riverdale, Roxboro, Stanley Park/Elboya, Sunnyside, Victoria Park, Westmount and Windsor Park.

The city of Calgary added the downtown core to areas being evacuated, due to the rising waters and power blackouts. The Calgary Zoo has also been effected, according to their Facebook page, with keepers moving many of the animals to higher ground, and two pot-bellied pigs and two zebras being moved to other locations.

[ Related: Calgary flood evacuation grows, zoo's lions and tigers could be next ]

There are numerous roads and bridges closed in the city, and schools and businesses are closed today as well, and Calgary Mayor Naheed Nenshi is asking all residents to avoid any unnecessary travel.

The Town of Banff, already cut off from both directions as highways are closed, is the latest community to be be under a Flood Warning, due to rising waters on the Bow River. The town is sandbagging essential areas, and residents are being warned to stay away from the river.

In the city of Medicine Hat, a state of local emergency has been declared and officials are working on evacuating up to 10,000 people from vulnerable neighbourhoods, relocating them to Medicine Hat College by 10 p.m. tonight. Flooding hasn't reached the city yet, but water levels are expected to rise significantly.

The first community hit by the flooding was Canmore, west of Calgary on Highway 1A to Banff. The Cougar Creek overflowed its banks early Thursday morning, forcing road and bridge closures, and the evacuation of several neighbourhoods along the banks of the creek. Roads leading into the town are closed in both directions, as are roads into Banff.

Several other communities joined them throughout the day, as waters rose in High River, Black Diamond, Turner Valley and Bragg Creek.

[ Full coverage of the Alberta floods ]

Residents in High River were some of the hardest hit, as the water flowed over the banks of the Highwood River, forcing them to evacuate to the local high school. According to the Calgary Herald, RCMP in the area were reporting that as many as four people are dead: One woman who was swept downstream yesterday, when the trailer owned by her and her husband flipped over, has still not been found, two other bodies have been seen in the water, and another man was seen falling out of canoe, but it's unknown whether he was able to climb back in. Since then, the RCMP has confirmed that two bodies were pulled from the Highwood River, near High River, and another was located, but has not yet been recovered.

The water rose in the town so quickly that many people were forced to climb onto their roofs to escape it, and had to wait to be rescued. (Some even by combine!)

Those that did make it to the emergency centre needed to uproot themselves again when the flooding spread and the entire town was evacuated to Nanton, about 30 km to the south. According to the Calgary Herald, RCMP Sgt. Patricia Neely reported that 150 people had been rescued from their rooftops.

“This is a lot more significant than what we usually see," she said. "To have 150 people that were forced to roofs shows the speed and how quickly this flood came through.”

Local resident Mark Kent compared conditions to the last time there was major flooding in the area: "2005 doesn't even compare to what this is, that was just a puddle compared to what this is."

"Nobody was prepared for this," said Wayne Goodman, a resident of the area who helped evacuated around a dozen people on Thursday, according to the Calgary Herald.

"The system didn't work. It failed."

Others are angry about the way the town handled the situation.

"They started sandbagging, but by then it was too late. I am very angry," resident Teri Mans told the Calgary Herald. "I realize it is a state of emergency, but this town needs to get better prepared living this close to the Highwood River. It's ridiculous."

In Bragg Creek, now under a mandatory evacuation order, residents watched the river overtake their community. Some watched on in shock as an entire house was swept away to be smashed against a bridge:

Flooding wasn't the only danger in some communities, as a sour gas line ruptured in Turner Valley when debris in the water hit the pipeline, forcing residents to immediately evacuate the area. Sour gas is natural gas that contains a chemical called hydrogen sulfide, and hydrogen sulfide is highly toxic when inhaled. According to The Canadian Press, the gas was turned off in the pipeline, but as there was "still a bit of a trickle" under the water, the owner of the pipeline, Legacy Oil and Gas of Calgary, was deciding whether or not it's safe to send divers in to fix the leak.

[ Related: Nenshi, Redford and Harper showing strong leadership on Alberta floods ]

In addition to the evacuation orders in Calgary, Canmore, High River, Bragg Creek, Black Diamond and Turner Valley, several other communities have been evacuated, including Eden Valley, Bighorn and Morley, the Oldman River valley area in Lethbridge county, and the eastern half of Sundre. All told, a dozen communities throughout southern Alberta have declared states of emergency.

Authorities have opened the spill-way gates on dams at the Travers Reservoir and the Twin Valley reservoir in Vulcan county, to relieve the pressure building up from the flood waters. Anyone living downstream from these areas was advised to evacuate to higher ground.

According to CTV News, as of this morning, the 600 Canadian Forces members were deployed from Edmonton to help in the flood-ravaged areas of Canmore, High River and Kananaskis, and another 600 are expected to arrive later today.

"The military is going to call them in to help with the evacuation effort and then later to help with negotiating the terrain,” said Mercedes Stephenson of CTV News.

The rain causing this flooding continues in areas west of Calgary right now, adding to the waters already causing rivers and streams to swell. According to Environment Canada, rainfall amounts over the last 60 hours have have ranged from around 50 mm in Calgary, 75 mm in Lethbridge, 90 mm in Black Diamond, 116 mm in Sundre, and over 190 mm in Bow Valley. Heavy rain warnings are still in effect for regions just to the north and west of Calgary, and this rain is expected to slowly taper off tonight and into Saturday.

Donations to help those affected by the flooding can be made to the Canadian Red Cross (click here).

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