When to winterize sprinklers at Bear Lake (and what happens if you skip it)

The short version

Book the blowout for October. If you cannot be at the property, book it in September, because you will not be there to notice the forecast turn.

Why the timing is different here

Most irrigation advice on the internet is written for places where the first hard freeze is a November event. Bear Lake Valley sits at roughly 5,900 feet on a short season, and a hard freeze here can arrive in October and occasionally earlier. The valley does not run on a calendar date; it runs on the first night the temperature drops far enough, for long enough, to freeze water sitting in a pipe.

That is the whole problem. An irrigation system is a network of pipe, valves and brass sitting just under the surface, and after the last watering of the year it is full of water. Water expands when it freezes. Whatever is holding it, a lateral line, a valve body, the backflow assembly, is what splits.

What a blowout actually is

A winterization blowout pushes compressed air through each zone of the system, one at a time, until the heads run dry. The air pressure has to be high enough to clear the line and low enough not to cook the seals in the heads, which is why it is done zone by zone rather than all at once.

Done properly it takes a high-volume compressor, a quick-connect fitting on the system, and somebody standing at each zone watching the heads go from water to mist to nothing. It is not complicated, but it is not optional either.

What happens if you skip it

Nothing, at first. That is what makes it dangerous.

The system sits full of water through October. One night in late October or November it freezes hard. A lateral line splits under the lawn. The backflow assembly, which is the most expensive single piece of brass on the system and sits above ground, cracks. Nobody hears it. The snow comes and covers everything.

In April or May, somebody turns the water back on. A zone will not hold pressure. Water is bubbling up in the lawn where the line split. The backflow is leaking from a crack that was not there in September. What should have been a flat blowout in October is now a repair bill for labor, parts and, on a bad year, a backflow assembly.

For a full-time resident this is expensive and annoying. For an owner who lives four hours away and comes up in June, it can be a month of water running under the lawn before anyone notices.

The absentee owner problem

Roughly a third of the housing in Bear Lake County is seasonal. Those owners are not here to see the forecast, and the blowout list in this valley fills through October because everybody wants the same two weeks.

If that is you, the practical advice is simple: get on the list in September. You do not need to be at the property. A blowout needs access to the system and the controller, and a way to reach you if something needs a decision. Ask for confirmation when it is done and you will get it.

What the blowout finds

The other thing a blowout does is put eyes on the system at the end of the season. Heads that have been spraying the driveway all summer, a zone that has been coming on twice, a controller that lost its program in a power cut. None of that is the blowout’s job, but it gets noticed, and it is easier to fix in October than to discover in May.

Backflow, plainly

One honest note: replacing a backflow assembly and testing one are different things. Northbound replaces them. Testing is a separate certification we do not hold yet, so it is referred to a certified tester until we do. If your water provider requires an annual backflow test, that is a separate appointment from the blowout.

Book a sprinkler blowout, or read the irrigation page for maintenance and the links to startup and repair.