Canmore has always been susceptible to flooding given its low-lying location on the Bow River floodplain. For people who lived near the river on both sides of Canmore, flooding was a simple fact of life. Provincial records indicate the Bow River has flooded at least 19 times between 1883 and 1967 with a number of those inundating Canmore, specifically Mineside, with water.
But on Tuesday, June 25, 1974, with warm June weather and an unusually heavy snowpack, the Bow River began to flood causing Canmore’s mayor and doctor, Alfred Miltins, to declare a state of emergency. The flood’s crest, which was expected on Thursday, was going to be larger than anticipated as Calgary Power had been forced to release water from Lake Minnewanka to keep it from overflowing.
The Calgary Herald reported the water level could rise an additional nine inches to a flood that was already six feet higher than the normal level of flow for the Bow River, and at 13,276 cubic feet per second, it was a flow amount only recorded once every 10 to 15 years.
By Wednesday, the Calgary Herald reported the flood had affected nearly 95 per cent of Canmore’s 600 homes, with Eighth Avenue, Second Street and Mineside the worst hit. A handful of families had to be evacuated.
Hundreds of volunteers laboured throughout the day and night filling the 40,000 sandbags needed to build a three-kilometre-long dike to keep the brown flood water from spreading further into town. Children even sacrificed the sand in their sandboxes as they helped their parents to fill the burlap sacks that would make the 50-pound sandbags.
The flood of 1974 spurred officials to build the Bow River dike that stretches along from east of First Street in South Canmore west along the river to the end of Larch Avenue. The dike also runs along a relatively short section of the south bank of the river to protect homes in the Mineside area, has protected Canmore since its last big flood. The dike is designed to protect from all but that one per cent flood, a flood so large that only occurs one per cent of the time in any year.
Taken from The History of Canmore, by Rob Alexander, published by Summerthought.