Photo of work being performed in Banff, Alberta in October
November 17, 2017.
With the snow already on the mountains, the irrigation season in the Calgary area, comes to a quick halt. As water freezes at 0C, a concept for some people in Calgary, the irrigation portions above ground freezes up quickly. Underground sprinkler systems are required to be winterized in climates where the ground freezes. Calgary and area is one of those places.
The winterizing procedure is done by connecting at minimum a 185 cfm air compressor to the sprinkler system and "blowing out" all the water. Although it is impossible to remove all the water, the majority is pushed clear out of the system, that way when the little water that remains freezes, it does not damage the sprinkler components.
Although a sprinkler blowout is occasionally possible after the temperatures dip below zero, it all depends if the ground freezes before a chinook wind blows in an warms things up. Most likely some small damages do occur.
In Calgary, most irrigation systems are installed using polyethylene pipe which is a black pipe that stands up to the freezing temperatures better then PVC pipe (a white plastic)
Next Rain Irrigation routinely does installations until the ground is completely frozen, which is typically a week or two after the first harsh freeze, usually below minus 7C.
Irrigation drip line installed in Banff
Dripline installed after first snow