The short answer
Backflow is when used or contaminated water reverses direction and flows back into your clean drinking-water supply. A backflow preventer stops it. Because the health risk is real, Georgia and local water authorities require many of these devices to be tested by a certified tester.
What is backflow, exactly?
Your plumbing is designed to flow one way — clean water in, waste water out. Backflow is when that direction reverses and non-potable water gets pulled or pushed back into the clean supply.
It happens for two main reasons: back-siphonage (a drop in supply pressure, such as during a water-main break or heavy fire-hydrant use, that sucks water backward) and back-pressure (downstream pressure, such as from a boiler or pump, that pushes water backward).
Where is the risk in a typical property?
Common cross-connections where backflow can contaminate drinking water:
- Irrigation and sprinkler systems
- Boilers and certain heating systems
- Hose bibs left submerged (a hose in a pool, bucket, or chemical sprayer)
- Commercial equipment and some water-using appliances
What does a backflow preventer do, and why test it?
A backflow preventer is a valve assembly that mechanically blocks reverse flow. Like any mechanical device, its internal checks and springs can wear out — and a failed preventer offers no protection while still looking fine from the outside.
That is why testing exists. A certified backflow tester verifies the assembly holds and reports the result to the water authority.
Why it's required
Georgia's plumbing code and local water purveyors require backflow prevention on many connections and periodic testing (commonly annual) to protect the public water supply. Your exact testing schedule is set by your local water authority — confirm your due date with them or with us.
Who can test a backflow device?
Backflow testing must be done by a certified tester using calibrated gauges. Head's Plumbing is Backflow Certified and tests, repairs, and installs preventers across metro Atlanta — and we keep your paperwork straight with the water authority.
Many jurisdictions require annual testing, but the exact schedule is set by your local water authority and the type of connection. We can confirm your requirement and keep you on schedule.
Often yes — especially with irrigation systems, which are a common residential cross-connection. Your water authority determines whether your property's device is on a required testing schedule.
The assembly usually needs repair or replacement, then a re-test. A certified plumber can rebuild many devices on site and re-test to bring you back into compliance.
Terms in this guide
- Backflow preventer
- A valve assembly that stops dirty or contaminated water from reversing direction and flowing back into your clean drinking-water supply. Georgia requires many of these devices to be tested by a certified tester on a regular schedule.
- Pressure-reducing valve (PRV)
- A valve that lowers and stabilizes incoming municipal water pressure to a safe level (typically 50–75 PSI). Too-high pressure stresses fixtures, water heaters, and joints, and can void appliance warranties.