What to Expect During Your Sprinkler Winterization — A Step by Step Look at What We Do

As we move into October and overnight temperatures start flirting with the freezing mark, the phones at Alternate Rain are ringing with one question more than any other — "when can you come out to winterize?" We're starting winterizations next week, and for homeowners who have never been through the process before or aren't quite sure what actually happens during the visit, here's an honest, straightforward look at what our technicians do from the moment they pull up to the moment they leave.

Why winterization matters — a quick refresher

An irrigation system that isn't properly prepared for winter holds water in its underground pipes, heads, valves, and backflow preventer. When that water freezes it expands, and that expansion puts enormous pressure on everything it's sitting in — cracking pipes underground, splitting valve bodies, breaking heads, and damaging the backflow preventer. The repair costs in spring can far exceed what winterization costs in fall, which is why we encourage every customer to get it done before the first hard freeze rather than after.

The blow-out process — how it works

The majority of winterizations we perform each fall involve blowing the system out with a commercial air compressor. Most irrigation systems installed in the Omaha area hold water in their underground lines after each watering cycle. Getting that water out before it freezes requires forcing compressed air through each zone to push every drop out of the pipes, heads, and fittings.

When your technician arrives they'll connect a commercial air compressor to the system at the blow-out port — typically located near the backflow preventer. The compressor we use is significantly more powerful than a standard shop compressor, capable of delivering the volume of air needed to clear a full zone of pipe and heads in one pass.

With the compressor connected, the technician runs through the system one zone at a time. Each zone is opened individually at the controller while compressed air is forced through the line. You'll see the heads pop up and a mist of water and air come out — that's exactly what's supposed to happen. Each zone typically runs for two to three minutes, which is enough time to fully clear the water from the pipes and heads. The technician watches each zone carefully to confirm the line is fully evacuated before moving to the next one. This process is repeated for every zone in the system.

Why it takes the time it takes

Homeowners sometimes wonder why a blow-out takes as long as it does. The answer is straightforward — every zone needs its own dedicated time to fully clear. Each zone runs for two to three minutes to push all the water out of the pipes and heads completely before the technician moves on to the next one.

The backflow preventer

Once every zone has been blown out, the technician turns attention to the backflow preventer — the device located above ground where your irrigation system connects to your home's water supply. The technician will shut off the water supply to the irrigation system, then open the drain ports on the backflow preventer to release any water sitting inside the device. The backflow preventer stays in place through the winter — it simply needs to be fully drained and left in the winterized position to protect it from freezing. A frozen and cracked backflow preventer is one of the more costly single repairs on an irrigation system, so this step is never skipped.

Walking the zones

After the blow-out is complete, the technician will do a visual check of accessible heads and zones — particularly any areas flagged during the season or where obvious damage is visible. Fall is actually a good time to catch issues because the lower sun angle makes wet and dry coverage patterns easier to identify, and the end of the season is the right time to note anything that should be addressed before spring startup.

If the technician finds a head that's cracked, stuck in the up position, or clearly damaged, they'll note it and let you know. Minor issues can sometimes be handled on the spot. More significant repairs are typically scheduled for early spring so everything is ready to go when the system starts back up.

The controller

Before leaving, the technician notes your controller's current programming so your spring startup can be configured correctly without reprogramming from scratch. If your controller has a seasonal adjust or off setting, it may be set to the dormant position for the season.

What you can do before we arrive

A few things make the visit go more smoothly. Know where your irrigation shutoff valve is — typically in your basement or utility room — and make sure it's accessible. If you've noticed specific zones or heads that weren't performing well during the season, jot them down. And if you have a dog with yard access, securing them before the appointment is always appreciated.

What comes next

Once your system is winterized it goes dormant until spring. When temperatures stabilize after the last frost — typically late March through April in Omaha — it's time for your spring startup visit. That's when we turn the water back on and run through every zone to make sure everything is operating correctly heading into the new season.

If you're enrolled in our Seasonal Care Package, your winterization and spring startup are already included — no need to call or remember, we handle the scheduling. If you're not yet on a package and want to simplify your annual irrigation maintenance, ask us about it when we come out.

Ready to get on the schedule? Give us a call at (402) 289-4019 or contact us online. Spots are filling up and we want to make sure every customer is protected before the first hard freeze arrives.