Seasonal care · fall & winter

Sprinkler winterization in North Texas: protect the backflow before the freeze.

Here's the good news: you don't need the full compressed-air blow-out the northern states do. Here's the part people skip anyway: you absolutely have to protect the backflow assembly, because it sits above ground, holds water, and is the first thing to burst when a hard freeze hits. The February 2021 freeze cracked thousands of them across the metroplex. This is the cheap fall job that prevents the expensive spring repair.

Why winterizing here isn't a northern blow-out

In hard-freeze climates, every drop of water gets cleared out of the system with compressed air, because the ground freezes deep and anything left will crack. North Texas is a different problem. Our freezes are shorter and the ground rarely freezes deep, so buried lines are usually fine — the real exposure is what sits above ground: the backflow assembly, exposed risers and heads, and anything holding pressurized water. So winterizing here means protecting those exposed parts and being ready to shut down for a freeze, with a full blow-out as optional extra insurance for some systems rather than the default.

How to winterize, step by step

1. Get ahead of the first hard freeze. Usually late November into December — but watch the forecast, not the calendar, because the date moves every year.
2. Shut off the water to the irrigation system. Close the isolation valve between the meter and the backflow. The rest of the house keeps water; the sprinkler side stops taking on more.
3. Relieve the pressure. Open a drain or the test cocks on the backflow so trapped water has somewhere to go instead of expanding against the assembly when it freezes.
4. Insulate and cover the backflow. Wrap the assembly in insulation and cover it with an insulated pouch or a permanent cover. This is the step that actually prevents the burst.
5. Set the controller to off. Or rain mode — so the system doesn't try to run in freezing weather.
6. Decide on a blow-out. For some systems, or for real peace of mind, a compressed-air blow-out clears the lines too. It's optional here and best left to someone who won't over-pressurize and crack things — but it's a reasonable upgrade.

The freeze-day plan

Winterizing once in the fall isn't quite the whole story in North Texas, because we get warm spells between freezes. Keep a simple plan: know exactly how to shut the system off fast when a hard freeze is forecast, and how to drop the backflow's pressure. On the warm, dry stretches in between, you can run a little foundation watering — the clay keeps drying through a mild winter, and a light drink keeps it from shrinking away from the slab. Then shut it back down ahead of the next freeze.

What happens if you skip it

The usual outcome is a cracked backflow you discover at spring start-up — which means a replacement, and a failed backflow test until it's fixed. Exposed heads and shallow risers can split too. None of it is a disaster, but it's entirely avoidable, and here's the part that stings: during a widespread freeze, every irrigation and plumbing outfit in the metroplex has the same emergency, the repair queue stretches for weeks, and parts go scarce. The thirty-minute fall job is a lot cheaper than the spring scramble.

If you'd rather have it done right — backflow protected, system shut down properly, a plan in hand for the cold snaps — that's a quick visit, and a good one to bundle with the rest of your seasonal care.