Sprinkler System Winterization

What is a Winterization?

Why you should blow out your sprinkler system in Utah

In Utah County and Salt Lake County, winter temperatures can be unpredictable: some years we have warm winters, and some years they are unbearably cold. When winter weather gets bad, the pipes in your sprinkler system can burst, causing leaks and damage to your home. A professional sprinkler winterization is the best way to prevent this issue. We turn off your water supply and blow out all of your sprinkler lines with high-pressure air to remove as much water as possible.

Some homeowners choose to winterize their sprinkler systems themselves either by turning them off and allowing them to drain or blowing them out with a small air compressor. Hiring a professional is more convenient, more thorough, and will give you peace of mind compared to doing it yourself.

Steps to Winterize a Sprinkler System

1. Shut off the water — For most homeowners, the main shutoff valve for a sprinkler system is either in their basement or in the yard near the home's water meter. Some valves are self-draining (stop and waste valves) while others are not. It is important to know which type you have. In pressurized irrigation (secondary water) cities like Spanish Fork, Pleasant Grove, Alpine, and Bluffdale, the city will shut off the water as well, but it is good to shut it off at your own system for safety. Most cities shut off secondary water on October 15. We recommend winterizing your system between October 1-31.
2. Winterize the backflow preventer — For lawn irrigation systems running on culinary water, backflow preventers are generally required by local building codes. These come in various shapes and sizes and can be above ground or below ground. The purpose of a backflow preventer is to prevent contaminated water in the irrigation system from flowing back into the drinking water supply. Each backflow preventer is different in winterization steps, so it is best to find an online manufacturer guide for your specific model. Most follow a few main steps: shut off the water supply, shut off the outlet valve, open drains and test cocks, blow out the pipes, and set valves to half-open for winter. Important note: systems running on secondary water (pressurized irrigation) do not need backflow prevention, so this step can be skipped depending on your city.
3. Blow out pipes, valves, and sprinkler heads — Blow out each sprinkler station, one at a time, by hooking an air compressor into the main line and running a sprinkler cycle for about 5 minutes per station. An air compressor can attach through a spigot or winterization port. Some systems have automatic drains, but many contractors advise against relying on these because they can fail. On most residential systems, a small 30-gallon air compressor is sufficient. Backflow preventer outlet valves should be closed during this process to avoid damaging internal components.
4. Set controller to off position — Some controllers, such as Rachio controllers, call this "hibernation mode." This stops electrical signals from flowing to the valves. However, if you forgot to turn the controller off, it is okay. Just make sure the water is turned off! Turning off the sprinkler system from the controller does not prevent freeze damage—the water supply itself needs to be turned off.
5. Keep the water off until it gets warm again — There is no reason to water your lawn between October and March. Utah landscapes generally use cool-season grass like Kentucky bluegrass and tall fescue. To avoid freeze damage or wasting water, don't turn on your sprinklers until it warms up again. The best time to turn your sprinklers on in Utah is in April.