Your building has a device that keeps dirty water from flowing backward into the public water supply. That device has to be tested on a schedule. Here is what backflow is, why testing matters, and what you need to do to stay compliant and safe.
Nobody wants water from a cooling tower, a sprinkler system, or a mop sink flowing backward into the same pipes that supply drinking water. Backflow prevention devices are installed to stop that from happening. But those devices can fail or wear out. Testing them regularly is how you confirm they still work and how you satisfy local rules that apply to commercial properties across the Southeast.
What Is Backflow?
Normally, water flows from the public supply into your building. Backflow means water flows the wrong way: from your building (or your site) back toward the public system. That can happen when pressure in the public line drops, for example during a main break or heavy use, and the pressure in your building is higher. Without a working barrier, water from your side can be pulled or pushed into the community supply.
That water might come from irrigation, boilers, cooling equipment, fire sprinklers, or industrial processes. It can contain chemicals, bacteria, or other contaminants. A backflow preventer is a mechanical device installed on your water line that is designed to allow flow in only one direction. When it is working correctly, it blocks reverse flow and protects the public supply.
Why Testing Is Required
Backflow preventers have internal parts that can stick, break, or leak over time. If they fail, they may not stop reverse flow when it matters. Testing is a check that the device still opens and closes as intended and holds the correct pressure differential. Many cities and water utilities require commercial (and sometimes multi family) properties to have backflow devices tested every year, and to submit a test report by a certified tester. Skipping the test can lead to fines, loss of water service, or in the worst case, liability if contaminated water ever reached the public system.
Even when testing is not strictly required by your utility, having it done on a regular schedule is good practice. It gives you a record that you maintained the device and helps catch problems before they become emergencies.
What Happens During a Test?
A certified technician will:
- Locate the backflow preventer (often near the water meter or where the main enters the building).
- Connect test equipment to the device and run it through its operating cycle.
- Measure pressure and check that the device holds properly and does not allow reverse flow.
- Record the results and, if required, complete the form your water provider uses for submission.
Testing usually takes a short time per device. If the device fails the test, the technician will tell you whether it can be repaired or must be replaced. Repairs or replacements are separate from the test and may be scheduled right away to avoid compliance issues.
Who Needs Backflow Testing?
Requirements vary by location, but in general:
- Commercial buildings with a reduced pressure or double check assembly on the incoming water line are typically required to test every 12 months.
- Properties with irrigation, fire sprinkler systems, or industrial process water often have one or more backflow devices that must be tested annually.
- Some jurisdictions require testing when a property is sold or when a new device is installed.
Your water utility or local code authority can confirm the exact schedule and submission process for your address. In the states we serve, including Florida, Georgia, Tennessee, and North Carolina, annual testing is common for commercial sites. Scheduling the test early in the year helps you avoid a last minute rush and possible penalties.
Stay on Schedule and Keep Records
Put backflow testing on the same calendar as your other facility maintenance. When you receive the test report, keep it on file and send a copy to the water provider if they require it. If you manage multiple sites, track each device and its test date so none are missed. A single missed test can trigger a notice or fine; recurring misses can lead to more serious consequences.
Garrett Mechanical offers backflow prevention and testing for commercial properties across the Southeast. Our technicians are certified to test and repair backflow assemblies and can help you stay compliant. If you are not sure when your device was last tested or whether you have the right devices in place, contact us. We can schedule a test and walk you through the results and any follow up your building needs.