When my brother lived in Arizona he used to laugh about that. When below freezing overnight temps were predicted they'd say "Cover your swimming pool so that it doesn't freeze." I never took physics, yet even I know how crazy that is.
The pool might not freeze. but the sprinklers might.
I was living in Las Vegas when they had the first day on record when it didn’t get above freezing. Nearly every house, office, or building of any kind has a sprinkler system that they don’t winterize, and that is above ground. At that time they were still sprinkling bushes in the middle of the freeway, and that froze, burst and then flowed across I-15 turning into ice. And, a fun time was had by all.
The second night the sprinkler manifolds all started bursting as they froze. Most folks had no idea how to turn their sprinkler system off. Some installed by handymen and homeowners didn’t have separate shut offs, other than the one for the entire house.
The Water District, sent any employee who could walk out with valve wrenches, to shut off the meter to any house that had water running to the gutter. There had been so much water flowing that reservoirs were emptying and they no longer had fire flow pressure in parts of the valley.
I was living in a rental, going to college. The first night, when they warned it might freeze, I went out and put my biggest Coleman cooler upside down over the sprinkler manifold, unplugged the sprinkler clock, and plugged in a drop light with a 100-Watt bulb and put it under the cooler with the sprinkler manifold, then threw an old sleeping bag over the top. The Landlord called to say he couldn’t get over to fix my sprinklers for a couple of days. He was very relieved when I told him that the pipe didn’t freeze. And, when I told him that we had already dug down and installed a shutoff valve on the feed line, he took $200 off the rent. Many beers, and much pizza were had by all…
