How to Winterize Your Sprinkler System in North Texas (and Spot Freeze Damage)
Updated: Oct 8
In North Texas, winterizing a sprinkler system comes down to three jobs: shut off the irrigation water supply, drain and insulate the backflow preventer, and keep the controller from running during freezes. You rarely need the full air blowout used in colder states, but skipping these steps can leave you with a cracked backflow device after the first hard freeze.
This guide walks through each step, then covers the freeze damage to look for once temperatures climb again. If you'd rather hand the job off, our sprinkler winterization and maintenance service covers everything below.
Do Texas Sprinkler Systems Need Winterizing?
Fort Worth winters are mild most days, but the area still gets hard freezes. The February 2021 winter storm showed how much damage a few days below freezing can do to plumbing that was never protected.
The good news is that buried sprinkler lines are rarely the problem during a typical DFW cold snap, because the ground here doesn't freeze deeply. The parts at risk sit above ground or close to the surface:
The backflow preventer. This is the brass assembly where your system connects to the water supply. It sits above ground, holds water, and is the part that cracks most often.
Exposed pipe running into and out of the backflow preventer.
Valves and heads in low, wet spots, where water can freeze inside the body.
So yes, your system needs winterizing, but it's lighter work than in northern states. The goal is to protect the exposed parts and keep the system from running when it's below freezing.
Step-by-Step Winterization Checklist
Turn off the irrigation water supply. Look for the shut-off valve in a small box near your water meter or just before the backflow preventer. Closing it takes the system off pressure.
Set the controller to off or rain mode. Leave it powered so it keeps your watering program, but stop it from running on a freezing morning.
Photograph your controller settings. A quick photo of each zone's schedule makes spring start-up easy if the program is ever lost.
Drain the backflow preventer. With the supply off, slowly open the small test cocks partway to release trapped water. If you're not sure which valve is which, leave this step to a technician; a damaged or misadjusted test cock can cause a leak in spring.
Insulate the backflow preventer and exposed pipe. Use foam pipe insulation plus an insulated backflow cover or bag. Plastic wrap alone doesn't insulate and traps moisture.
Check your rain/freeze sensor. If your system has one, make sure it's connected and working. If it doesn't, ask about adding one so the system shuts off automatically when temperatures drop.
Protecting Your Backflow Preventer from Freezing
Your backflow preventer keeps irrigation water from flowing back into your home's drinking water. Texas requires one on irrigation systems connected to a public water supply, so it isn't optional equipment.
Because it sits above ground and stays full of water, it takes the full force of a freeze. When that water expands, the brass body or internal parts can split. Replacing a cracked backflow preventer costs far more than an insulated cover, and a broken one can leave your system out of service until it's repaired.
A few habits make a big difference:
Put the cover on before the first forecast hard freeze and leave it on through February.
Make sure the cover reaches the ground so wind can't get underneath.
After a freeze, check the backflow preventer before you turn the water back on. If you see a crack or water spraying from it, keep the supply off and call for repair.
Should You Water Your Lawn in Winter?
Most Fort Worth lawns are warm-season grasses such as Bermuda, St. Augustine and zoysia, which go dormant in winter. Dormant grass needs far less water, but not none.
In a dry winter, a deep watering every few weeks helps the roots and keeps the soil around your slab from drying out and shrinking. Our post on keeping soil moisture around your foundation explains why that matters in Texas clay.
When you do water, pick a mild day and water mid-morning, when temperatures are well above freezing. Never water right before a freeze, because wet sidewalks and streets turn to ice. Many North Texas cities limit outdoor watering, so check your city's current schedule first. If your system is shut down for winter, a hose or a short manual cycle on a warm day does the job.
Signs of Freeze Damage After a Hard Freeze
Once temperatures are back above freezing, turn the supply on slowly and run each zone one at a time. Watch for:
Water spraying or dripping from the backflow preventer. This is the most common freeze failure. Shut off the supply and call for repair.
A geyser or bubbling water in the lawn. Usually a cracked pipe or fitting underground.
Low pressure in a zone. Heads barely pop up or the spray falls short, often because of a hidden break.
Soggy patches that stay wet long after the zone shuts off.
A zone that won't turn on or won't shut off, which can point to a cracked valve.
Split or cracked sprinkler heads, especially in low areas.
Our guide to finding a leak in your sprinkler system shows how to trace these problems step by step.
Booking a Post-Freeze Inspection
Some freeze damage is obvious. Much of it isn't, and a small underground crack can waste water for weeks before a soggy spot gives it away.
A professional inspection after a hard freeze checks the backflow preventer, runs every zone, looks at each head and valve, and fixes what the cold broke before spring watering starts. We handle winterization and post-freeze repairs across Fort Worth and surrounding cities, including irrigation services in Keller and nearby Haslet.
Frequently Asked Questions
Do I need to blow out my sprinkler lines in Fort Worth?
Usually not. Air blowouts are standard where the ground freezes deep. In North Texas, shutting off the supply, draining the backflow preventer and insulating exposed parts protects most systems. If some of your lines run through unusually exposed spots, ask a technician to check them.
When should I winterize my sprinkler system in North Texas?
Before the first forecast hard freeze, which in the Fort Worth area often arrives in late November or December. Watch the 10-day forecast and finish the job a few days ahead, not the night the cold arrives.
Can I leave my sprinkler controller on in winter?
You can leave it powered, but set it to off or rain mode, or rely on a working freeze sensor. Running sprinklers in freezing weather can crack heads and coat sidewalks and streets with ice.
What does a frozen backflow preventer look like?
Usually a split along the brass body, or water spraying or dripping from it once it thaws. Turn off the irrigation shut-off valve right away and call a technician; the part normally needs repair or replacement.
Need your system ready before the first freeze? Bob's Landscape & Irrigation Solutions winterizes, inspects and repairs sprinkler systems across Fort Worth and nearby cities. Call 817-381-2128 or request a free estimate.
About the author: This guide was written by the team at Bob's Landscape & Irrigation Solutions. The company's founder started it in 2009 as a side business while teaching middle school engineering in Birdville ISD for 14 years, then took it full time. Today the team handles irrigation, drainage, retaining walls, dirt work and artificial turf across Fort Worth and surrounding cities.
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