Turning Off the Water Isn't Enough
Many people think shutting off the main valve in the basement is all it takes. It isn’t. Underground lines, valves, and sprinkler heads are built to hold water. Even after the supply is off, gravity leaves plenty of it sitting in the low points of your piping.
When a hard freeze pushes into the ground, that trapped water freezes. It expands with real force. Here’s what that can lead to:
- Shattered pipes: Frozen water splits underground lines right down the seam.
- Cracked valves and manifolds: Plastic and brass components in valve boxes are especially vulnerable. Often, you won’t discover the leak until you turn the system back on in May.
- Backflow damage: Your backflow preventer sits exposed to the cold. If it freezes, replacing it can run into the hundreds of dollars.
What Actually Happens During a Blowout
Clearing a system properly means forcing the trapped water out with high-volume compressed air. This process is called an irrigation blowout. It isn’t a job for a garage air compressor. Most consumer compressors don’t move enough air, measured in CFM, to fully purge the lines. Even if the pressure reading looks high, pockets of water get left behind. And those pockets still freeze.
A professional blowout is different. It uses industrial compressors, and technicians carefully regulate the air pressure. It needs to be strong enough to push water completely out through the sprinkler heads. At the same time, it has to stay controlled enough to avoid damaging the lines and components. Every zone gets cycled through until the system is fully dry.
Beat the Freeze, Not the Calendar
Timing matters more than people expect. You want to keep your system running long enough to support any fall seeding or landscaping work. But you also need it cleared out well before the ground locks up for good.
- The safe window: Across the Des Moines metro, early October through mid-November is the sweet spot for winterization.
- The danger zone: Waiting into late November or December is a gamble. Once you get consecutive days of freezing temperatures day and night, the risk of serious pipe damage climbs fast.
Don't Get Stuck in the Freeze Rush
Blowouts are in high demand. Once the first hard frost warning hits the news, schedules fill up fast across Waukee, West Des Moines, Urbandale, Clive, and Johnston. That’s why property owners who book in September or early October come out ahead. They lock in their spot before the last-minute rush, and the risk that comes with it.
A Small Step Now Beats a Big Bill Later
Winterizing your irrigation system costs far less than a cracked pipe or a damaged backflow preventer come spring. Maybe you manage a commercial property. Maybe it’s an HOA. Or maybe it’s your own backyard system in Grimes, Pleasant Hill, Altoona, Ankeny, or Norwalk. Either way, getting ahead of the freeze protects the investment you’ve already made.
Protect your irrigation system before the freeze hits. Schedule your blowout today.
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