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So Your Backflow Preventer Burst After a Freeze - What to Do (and What Not to Do) in Florida

February 13, 2026

So your backflow preventer burst after a cold Florida night.

You may have noticed water spraying near the irrigation connection, soaked ground around the device, or a complete loss of irrigation pressure. In some cases, everything looked fine until the system tried to run again - and then the problem appeared suddenly.

This situation is more common in Florida than many people realize. Backflow preventers are critical safety devices, but they are also one of the most freeze-vulnerable components of an irrigation system.

The good news is that this type of failure is usually manageable - and often preventable - when handled correctly.

Your Backflow Preventer Burst After a Freeze - What to Do

 

What a Backflow Preventer Does (and Why Freezing Is Such a Risk)

A backflow preventer is designed to protect the potable water supply by preventing irrigation water from flowing backward into drinking water lines. Because irrigation water can contain soil, fertilizers, and other contaminants, this device plays a vital role in public health and system safety.

In Florida, most irrigation backflow preventers are:

  • Installed above ground
  • Constantly filled with pressurized water
  • Exposed to open air with little natural insulation

When temperatures drop near or below freezing, water trapped inside the device can freeze and expand. That expansion creates internal pressure strong enough to:

  • Crack the body of the backflow preventer
  • Split internal check valves
  • Damage seals, springs, and relief components

In many cases, the damage isn't immediately visible. Problems often appear only after the system is pressurized again.

How to Tell If a Backflow Preventer Was Damaged by Freezing

Common signs of freeze damage include:

  • Water spraying or leaking when irrigation runs
  • Visible cracks in the brass or composite housing
  • Water leaking from seams or relief ports
  • Sudden or uneven loss of irrigation pressure
  • Wet soil around the device even when irrigation is off

It's not unusual for a backflow preventer to look intact until the next irrigation cycle activates.

What to Do Immediately After a Backflow Freeze Failure

If you suspect freeze damage, quick and correct action matters.

1. Shut Off the Irrigation Water Supply
Turn off the valve feeding the backflow preventer to stop active leaking and prevent additional damage.

2. Do Not Pressurize the System
Running irrigation through a damaged backflow can worsen internal fractures and flood surrounding areas.

3. Inspect Visually - Do Not Disassemble
Look for obvious cracks or leaks, but avoid dismantling components unless handled by a qualified professional.

4. Schedule a Proper Repair or Replacement
Backflow preventers are safety devices. Once freeze-damaged, internal components may no longer function correctly even if leaks appear minor.

Shut Off the Irrigation Water Supply

 

Can a Freeze-Damaged Backflow Preventer Be Repaired?

Sometimes - but not always.

  • Internal component damage may allow for a rebuild if the housing is intact
  • Cracked housings almost always require full replacement
  • Repeated freeze exposure weakens the device and reduces long-term reliability

Temporary patches or improvised fixes are not recommended. A backflow preventer must function correctly — not just hold water.

What NOT to Do After a Backflow Preventer Bursts

These common mistakes often create bigger problems:

  • X  Do not tape, seal, or "patch" visible leaks
  • X  Do not bypass the backflow device
  • X  Do not run irrigation "just to test it"
  • X  Do not delay repairs while continuing to irrigate

Because backflow preventers protect water quality, shortcuts create unnecessary risk.

Why Florida Irrigation Systems Are Especially Vulnerable to Freeze Damage

Florida irrigation systems are designed differently than systems in colder climates. Most do not allow full drainage or compressed-air blowouts.

As a result:

  • Water often remains trapped inside backflow assemblies
  • Even a single cold night can cause damage
  • Repeated exposure increases failure risk over time

Freeze preparation in Florida focuses on risk reduction, not complete elimination.

How to Reduce the Risk Before the Next Cold Event

Proactive steps can significantly reduce the chance of freeze damage:

  • Shut off irrigation water before freezing temperatures
  • Relieve pressure where applicable
  • Insulate backflow preventers with approved covers
  • Avoid plastic directly against metal surfaces
  • Remove insulation once temperatures rise to prevent condensation

For HOA and commercial properties, having a documented freeze-response plan greatly reduces emergency repairs and downtime.

The Bigger Picture: Protecting Infrastructure, Not Just Irrigation

A failed backflow preventer impacts more than watering schedules. It can:

  • Delay landscape recovery after cold stress
  • Create unplanned repair expenses
  • Interrupt service timelines
  • Raise compliance and safety concerns

Addressing the issue correctly protects both the landscape and the infrastructure that supports it.

Smart Freeze Response Starts With Informed Action

A burst backflow preventer can feel like a major setback - but it doesn't have to become a crisis.

Shutting down the system promptly, avoiding shortcuts, and making proper repairs ensures irrigation systems are restored safely and reliably.

At Allegiance Landscaping, our approach emphasizes education, prevention, and correct repair protocols - so systems recover the right way, not the fast way.

Destination: Excellence - even when temperatures drop.

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