Post-Winterization Irrigation Checklist Calgary: 12 Steps to Complete After Your Blowout

After your sprinkler system blowout in Calgary, there are 12 things you should verify before you close the season completely. Most homeowners assume the technician’s departure means the job is done — and it largely is. But these quick checks protect your investment, ensure your system is ready for spring startup without surprises, and catch any issues the technician flagged before winter weather arrives.

Why Run a Post-Winterization Checklist?

A professional sprinkler blowout performed by J.G. Irrigation removes water from your system and leaves it ready for winter. But the post-winterization window — the 24 to 72 hours after your blowout — is when you have the best opportunity to confirm everything is correct, address any flagged items, and set yourself up for a clean spring startup.

The 12-Step Post-Winterization Checklist

1. Confirm the Indoor Water Shutoff Is Off

The main irrigation supply valve inside your mechanical room (or utility area) should be fully closed. Turn it clockwise until it stops. This valve should stay off until your spring startup in May. Do not leave it partially open.

2. Drain Any Remaining Water from the Backflow Preventer

The backflow preventer assembly (usually mounted on the exterior wall of your house) should have both shutoff handles positioned at 45 degrees to the pipe — not parallel (open) and not perpendicular (closed). This 45-degree position leaves the valve body slightly open, allowing any residual moisture to escape rather than freeze and crack the brass body.

3. Check the Backflow Preventer for Moisture or Cracks

Look at the brass body of your backflow preventer. Any visible moisture, dripping, or hairline cracks are signs of a problem. If your blowout was completed correctly and the device was installed in the past few years, this should be dry. Note anything unusual and contact J.G. Irrigation at 587-433-4795 if you see cracks — a cracked backflow preventer will not survive winter.

4. Verify the Controller Is Set to Off or Rain Delay

Your irrigation controller should be set to either Off or Rain Delay for the winter. Do not unplug it entirely — most controllers store their programming in memory that can be lost if power is disconnected. Set the dial or toggle to Off/Rain Delay and leave power connected.

5. Review the Technician’s Service Record

J.G. Irrigation leaves a written service record at your door after every blowout. Review it. It lists: zones completed, any issues observed, and any recommended repairs or concerns for spring. This is your starting point for the spring startup appointment.

6. Note Any Heads That Were Flagged

If the technician noted any broken, sunken, or misaligned heads, note them now while you can see the yard easily before snow covers everything. Taking a photo of flagged head locations helps your spring startup technician find them immediately.

7. Check the Valve Boxes Are Clear and Covered

Your green valve boxes should have their lids fully closed. A missing lid exposes valves to frost, debris, and snow melt. If any lid is damaged or missing, replace it before the first hard freeze. Replacement lids are available at most irrigation supply stores for $8 to $20 depending on size.

8. Walk Your Property Looking for Standing Water

In the 24 to 48 hours after your blowout, walk your yard and look for soggy patches or standing water. If a lateral pipe or valve was not fully cleared, residual water will pool. Contact J.G. Irrigation if you find unexplained wet spots — water in the ground near your pipes needs to be addressed before the first hard freeze.

9. Note Your Zone Count for Spring

Confirm with your service record or your controller how many zones your system has. This information is useful for spring startup scheduling, and helps you quickly verify that all zones fire correctly when the system is reopened in May.

10. Coil and Store Any Hoses Connected to Outdoor Taps

Your irrigation system’s winterization does not include garden hoses still connected to outdoor taps. Disconnect and store all hoses. If any outdoor tap has a separate shutoff inside the house, close it and drain the tap by opening it briefly before closing.

11. Document Anything That Needs Repair Before Spring

Now is the best time to note needed repairs while the season is fresh. Common flagged items: a head that was consistently poorly aimed, a zone with lower pressure than the others, a valve that was slow to close. Write these down and mention them when you book spring startup — J.G. Irrigation can come prepared with the right parts for same-visit repair.

12. Book Your Spring Startup Now

Calgary spring startup slots fill in April. The best time to book is right now — immediately after your fall winterization, before you forget and before the spring rush begins. Call J.G. Irrigation at 587-433-4795 or submit an online inquiry. Your name is on the calendar for May and you do not need to think about it again until spring.

What Happens If You Skip These Checks?

Most homes that skip the post-winterization check are fine — a properly completed blowout by a certified technician with a 185 CFM compressor leaves very little to go wrong. The most common issue caught by this checklist: a controller still set to Auto mode, which can trigger zones even with no water in the lines (no damage from this, but it wastes controller cycles and creates confusion in spring when you try to diagnose why certain zones did not repressurize as expected).

Post-Winterization Checklist — Costs & Next Steps

Action After Blowout	Who Does It	Cost
Confirm all zone valves closed	Technician during blowout	Included
Set controller to “Off” or “Rain” mode	Technician	Included
Insulate exposed backflow preventer	Homeowner / tech	$0–$30 foam cover
Note any heads needing spring replacement	Technician report	Report provided
Book next spring startup	Homeowner	$80–$200 (May)