One overlooked freeze can undo a full season's care.
If water is left sitting in your irrigation lines when temperatures drop, it has nowhere to go as it freezes and expands — putting real pressure on pipes, valves and fittings that were never designed to hold ice.
A professional winterization clears every zone with compressed air before the first hard freeze, so your system comes through winter the way it went into it.
That's how much water expands when it freezes.
Left in the system, that expansion is enough to crack pipe walls, split valve bodies and force fittings apart — damage that often isn't found until the system is started back up in spring.
The winterization process.
Shut Off the Water Supply
We close the irrigation supply valve so no additional water can enter the system once it's cleared.
Connect the Air Compressor
A compressor is connected at the system's inlet, sized correctly for your pipe diameter and zone layout.
Blow Out Each Zone
We cycle through every zone in turn, using compressed air to force remaining water out through the heads.
Drain & Protect the Backflow Device
The backflow preventer is drained and, where needed, insulated against the season's coldest stretches.
Power Down the Controller
We set your controller to its winter/off setting so it's not calling for water once the system is shut down.
Winterization FAQ.
What happens if I skip winterization?
Any water left in the system can freeze and expand, which is one of the most common causes of cracked pipes, split valves and damaged backflow devices — often turning into repair costs well beyond the price of a winterization visit.
Can't I just shut off the water myself?
Shutting off the supply is only part of it — water still sitting in the lines, valves and backflow device needs to be cleared out with compressed air. Without that step, the system isn't actually protected.
When should I book?
Ideally before your area's first hard freeze. We book winterizations through the fall, and earlier bookings get first choice of appointment times.
Do you winterize systems you didn't install?
Yes. We winterize irrigation systems regardless of who originally installed them.
Serving London & Surrounding Areas
Water Works Irrigation provides winterization service throughout London, Ontario and the surrounding communities. Get in touch to find out if your property is within our service area.