Flood waters crest in Medicine Hat, communities downstream prep for the worst

Low-lying neighbourhoods in Medicine Hat experienced flooding as the massive surge of water works its way through …
Some residents of Medicine Hat, Alberta are breathing a sigh of relief after reports came in that water levels on the South Saskatchewan River had crested on Sunday, however, with flood conditions projected to last for the next two days, many are no doubt wondering exactly what they'll have left when they return to those parts of the city inundated by this incredible surge of water.

Anxiety levels were high leading into Sunday, as residents watched the devastation in areas of the province upstream from them, with all that water from the Bow River, Highwood River and Oldman River dumping into the South Saskatchewan River, which runs right through the middle of the city.

[ Related: 65,000 back in Calgary, flood risk continues in southern Alberta ]

10,000 people were evacuated from the low-lying parts of the city, and authorities and volunteers spent most of Saturday putting down walls of sand bags in the hopes of keeping the flood waters at bay. As the waters crested on Sunday, two of the city's bridges over the river were closed, but the RCMP reported that they managed to keep the Trans-Canada Highway bridge open, although they were advising people to avoid it, just as a precaution.

Although the rate of water through the river was initially estimated to be around 6000 cubic metres per second (that's roughly equivalent to the water from two and a half Olympic-sized swimming pools passing by any particular point in the river every second), the actual peak flow from Sunday night turned out to be around 5,450 m³/s — a bit more manageable amount, given their preparations.

"[Environment Canada] gave us a high number, which was actually a good thing," Medicine Hat Mayor Norm Boucher told CBC News. "Sometimes when you scare us, then we can prepare at the higher level."

Despite this, some of the low-lying areas of the city have still experienced some flooding.

"We thought we had a good job there with the sandbagging but as it turns out when the water started to come in it sort of washed itself right in," Boucher said at a news conference, according to CTV News.

As we all witnessed back in 2005, when Hurricane Katrina hit the city of New Orleans, water has an unfortunate 'habit' of turning even the tiniest weakness in a dyke, levee or wall of sand bags into a massive breach. This is due to the simple nature of water as a liquid — as it can flow into even the tiniest cracks and crevices — but it's the incredible rate that the flood waters flow at, and the immense weight of the water, that is really the force that ends up thwarting our efforts to keep it under control.

[ More Geekquinox: How weather, geography made Alberta prime target for flooding ]

Downstream from Medicine Hat, communities along the river in Saskatchewan are bracing themselves for the worst effects of the flooding. The South Saskatchewan River winds its way northeast from Medicine Hat to Saskatoon, and then merges with the North Saskatchewan River to flow through central-eastern Saskatchewan and empty out into Cedar Lake, in Manitoba. According to Global News, Saskatoon seems to be fairing well, even with the high water levels in the river, but it's communities to the east of where the two rivers merge that are under the worst risk, and Cumberland House has been evacuated ahead of the anticipated flooding.

The weather forecast is calling for showers and thundershowers through southern Alberta today, which may add to the difficulties caused by the flooding, but for the most part, it looks like the weather will be giving people in the region the opportunity to start recovery efforts.

(Photo courtesy: Nathan Denette/The Canadian Press, Wikimedia Commons)

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