How to Winterize Your Sprinkler System: Sprinkler Blow-outs in Boulder County


Winterization is an important part of maintaining a properly functioning sprinkler system. Prepare your sprinkler system for winter by removing water from the sprinklers and pipes before winter freeze up. This is necessary to avoid costly repairs and replacements in spring.

Water freezing in the irrigation system will break the pumps, sprinklers, valves, fittings, pipes and other system components. Unfortunately, you may not be aware of these problems until you turn your sprinkler system in the spring.

In this blog post, we’ll take a look at the steps involved in winterizing your sprinkler system. Read on and have that peace of mind that you’ll have a sprinkler system that is ready to be re-opened in the spring.

Manual drain method

Drain the system by turning the irrigation system off. This will prevent more water from entering the system. Then, turn all the manual drain valves on.  These valves are usually located at the low points and end points of the piping of the sprinkler system. Water should drain out on its own after opening the valves. Open the drain cap or the boiler drain valve on the stop and waste valve once the water has drained out of the mainline.

Most sprinklers have check valves. If the sprinklers in your system have it, you’ll need to pull it up so that the water can drain out of the bottom of the sprinkler head.

Depending on the location of the drain valves, there could be some excess water in the sprinklers, piping or backflow even after you have completed the steps above. If so, you could try using a wet/dry shop vacuum to get any remaining amounts of water out.

Draining out the sprinklers, piping and backflow may take several minutes. Close the manual drain valves once the water finishes draining.