Dos and don’ts of winterizing irrigation systems

Know which sites are a priority so those irrigation systems can be winterized first. (Photo: Dennis’ 7 Dees)

Before temps dip below freezing, irrigation contractors need to properly shut down their customers’ irrigation systems. That means reserving air compressors for commercial properties and prioritizing which sites need to be winterized first. Follow these 12 dos and don’ts to prevent costly freeze damage.

Do

Schedule out shutdowns. List how many properties need a shutdown, the number of technicians needed, how many weeks until you expect a freeze and which sites are priorities (most likely to freeze first), says Matt Coombs, irrigation manager at Dennis’ 7 Dees in Portland, Ore.

Educate your team and customers. “Make sure techs know where the components are and that they aren’t skipping over anything,” Coombs says. “Actively talking to customers about components that need to be in place helps avoid damage and can be a revenue stream for us.”

Watch weather patterns. “Pay attention to extended weather forecasts, so you’ll know when to have it completed (before the first frost),” says Anthony Parsons, irrigation/enhancements manager at Landtech Contractors in Aurora, Colo.

Shut down from the point of connection and source. “Most systems will come from the point of connection to the backflow to the irrigation box,” Parsons says. “The mainline from the city will typically be in a basement or crawl space. Grab a bucket and port to unscrew and extinguish the water back through the wall to get it out of the pipes outside where it could freeze.”

Open as many valves as possible. “The most important are the ones downstream and uphill to get the air moving through,” Coombs says.

Hook up the compressor, and run each valve. Once the mainline is clear, start working on the valves back toward the compressor. “Make sure you’re blowing out through lateral pipes,” Parsons says. “When the heads stop misting, that’s when you’ll know you’ve got the water out of the lines.”

Plan for elevation changes. “Put the air compressor at the highest point of the property and hook it in there to push water down to the lowest area,” Parsons says.

Check air volume. “Put a pressure gauge on a coupler,” Parsons says. “Go in through the quick coupler port on the mainline to get the volume needed to blow the heads out.”

Be sure no
irrigation head is
left behind. All water should be pushed
out of the system. (Photo: Landtech contractors)

Don’t

Fail to put the valves at a 45-degree angle. “The side piece will catch water. Water will drain out through pockets on the side if they’re left perpendicular or parallel with the pipe. It will freeze every time,” Parsons says.

Run too many lines at once. That could cause you not to have enough air volume in the lines, Parsons says.
Stop before the last head finishes. “Watch the zones to make sure they get all of the water out of the system and push the heads down to make sure they’re stiff.”

Forget to get the volume out of all of the valves. “Copper splits in one area, but on a PVC system underground with a hard freeze, you could have spiral cracks 200 to 300 feet. You’ll have to trench a whole new line,” Parsons says.