Preventing another major flood in Alberta
CALGARY - A look at some of the major projects Alberta is considering to prevent another major flood:
Highwood River Diversion
What it would do: Divert water around the flood-prone community of High River when water levels on the Highwood River are high. Typically, in June, the Highwood flows at a rate of between 30 and 70 cubic metres per second. During the 2013 flood, the river peaked at between 1,500 and 1,800 cubic metres per second. The diversion would be designed to handle flows of 500 cubic metres of water per second.
What it would look like: There are three routes being considered — one that would take water north of the city, one that would take water south of the city, and one that would split north and south. It would be seven kilometres long. It would be 40 metres wide at its narrowest point and 200 metres wide at its widest.
Where this project sits: The government is currently consulting with residents and conducting an environmental review.
The Springbank Road Reservoir
What it would do: The reservoir would take water from the Elbow River and store it when levels are high, protecting Calgary and Rocky View County. Calgary can handle flow rates of 180 cubic metres per second downstream of the Glenmore Reservoir on the Elbow without having to sandbag. The peak flow rate of the Elbow River into the reservoir during the 2013 flood was 1,240 cubic metres per second. The reservoir would hold up to 59 million cubic metres of water.
What it would look like: The reservoir would sit 15 kilometres west of Calgary near Springbank Road, north of the river. A diversion weir would send water down a 4.5-kilometre canal to the reservoir.
Where the project sits: Some preliminary design work has been done. An environmental review is underway.
McLean Creek Dry Dam
What it would do: It would be used to control the Elbow River during periods of flooding and would protect the communities of Bragg Creek, the Tsuu T'ina First Nation, Rocky View County and Calgary.
What it would look like: The project calls for a 50-metre-high dam on the Elbow near McLean Creek, southwest of Bragg Creek. It would have a capacity of 49 million cubic metres during a flood.
Where the project sits: A conceptual design is complete, but the government says a decision to go ahead won't be made until it's determined whether an underground diversion in Calgary is feasible.
Calgary Underground Diversion
What it would do: It would take water underground from the Glenmore Reservoir to the Bow River.
What it would look like: The idea calls for an eight-metre diversion pipe to run under 58th Avenue S.W.
Where the project sits: A report is to come before a city council committee later this month that pegs the cost of the tunnel at $500 million.
(Source: Government of Alberta)