Backflow Testing & Prevention
Stop irrigation, pool and reclaimed water from flowing back toward the drinking supply.
Plumbing guide
Backflow Preventers for Irrigation in Peoria, AZ Homes
A backflow preventer keeps water from flowing the wrong way. Irrigation systems, which can sit in soil and fertilizer, are a common place for one.
By the Peoria Express Plumbing team ·
What backflow is
Water normally flows from the supply toward fixtures. A drop in supply pressure or a rise in downstream pressure can push it backward, so that whatever is in the irrigation line can enter the drinking water.
That is why plumbing codes require a barrier between irrigation and the home's supply.
Types of devices
Common devices include atmospheric vacuum breakers, pressure vacuum breakers, double check assemblies and reduced pressure assemblies, which are manufactured to ASSE listing standards such as ASSE 1013 for reduced pressure assemblies. The right one depends on the risk and the local rules.
Your water provider or building department can tell you which kind is required at your property.
Backflow devices compared
Which device fits depends on the hazard and on local code.
| Device | Typical use | Note |
|---|---|---|
| Hose bib vacuum breaker | Outdoor spigots | Screws on or is built in |
| Pressure vacuum breaker | Sprinkler systems | Installed above the highest outlet |
| Double check assembly | Irrigation and low hazards | Two checks in series |
| Reduced pressure assembly | Higher hazards | Has a relief port that discharges on failure |
Why testing matters
Springs, seals and check valves wear down. A device can look perfect and still leak backward, which is why many providers ask for regular testing by a certified tester.
Testers check that the device holds against reverse flow and report the result to the utility. Keep the paperwork.
Reclaimed water
Some areas supply reclaimed water for irrigation. This water is not meant for drinking, and cross-connections with the drinking supply are dangerous.
If your property uses reclaimed water, the lines are usually marked, and the rules on separation are strict. Do not connect anything yourself.
Signs of a problem
A device that leaks, spits water or has a cracked body needs service. A drop in pressure or odd water after irrigation runs can also point to a problem.
Freezing is rarely an issue in the valley, but heat, sun and landscaping equipment can damage exposed parts.
What a plumber can do
A plumber can install, repair, replace and test devices where licensed. The backflow testing and prevention page explains the work.
For landscape hose bibs, see the notes on a leaking outdoor spigot. Include the vacuum breaker in your inspection.
Homeowner routines
Keep the device clear of mulch and soil, and make sure the surroundings drain. Cover it with a box if the provider allows it.
Never block the relief port. Water spitting from it is a sign to call.
Commercial and new buildings
Commercial properties often face stricter rules, with testing logs and bigger assemblies. New construction needs installation before final inspection.
Questions to ask your water provider
Ask which devices the provider accepts, how often testing is due and which testers it recognizes. Ask whether reclaimed water is available on your street and what separation rules apply.
Keep a folder with the permit, the test reports and the device's serial number. A clear record saves time when the provider sends a reminder or when you sell the property.
If a notice arrives and you are unsure what it means, call the provider before the deadline passes.
How a double check assembly works
Two spring-loaded check valves sit in a row inside the body. Water pushes them open when it flows forward, and the springs shut them when flow stops or reverses.
Test cocks on the side let a tester measure the pressure drop across each valve. A weak spring or debris on a seat shows up as a failed reading.
Because the assembly relies on two valves, one failing does not immediately let water pass, which is why it suits lower-hazard connections.
How a reduced pressure assembly differs
This device adds a relief valve between the two checks. If either check fails, the relief valve opens and dumps water to the outside rather than letting it move toward the house.
That design makes it the choice where the hazard is higher. It also means the device needs space and a drain path, because it may discharge a good deal of water when it fails.
Install location matters. Keep it above grade and clear of standing water, as local code requires.
Seasonal care in the desert
Summer heat bakes plastic and rubber. Sunlight can crack exposed fittings, and landscape crews can strike a device with a trimmer. Check yours at the start of each season.
Look for wet soil around the base, mineral crust on the body and parts that wobble. These signs show a slow leak or loose fittings.
Shut the supply before you touch anything, and call a certified tester if you suspect a fault.
Choosing a tester or installer
Ask whether the person holds the certification your provider requires and whether they file results with the utility. A tester should bring calibrated gauges and give you a copy of the report.
Compare written quotes for repair, because replacement parts for some assemblies cost more than others. A repair kit is often enough when the body is sound.
What the state says
The Arizona Department of Environmental Quality page on Backflow Prevention and Cross-Connection Control says required assemblies must be tested at least once a year by a certified tester. It cites the Arizona Administrative Code, R18-4-215, and says ADEQ approves the bodies that certify testers.
Common questions
Backflow questions
Most irrigation systems connected to a potable supply require one. Check local rules.
Utilities often require it yearly. Ask your provider.
Many places require a licensed installer and certified testing. Check local requirements.
Related services
Commercial Plumbing
Restrooms, kitchens and water systems kept working in shops, offices and rental buildings.
New Construction Plumbing
Plumbing for a new house or addition, from slab trenches to the last fixture hookup.
More plumbing guides
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Water seeping from an outdoor faucet is wasted, and may point at a larger fault. See where it escapes and which part to change.
Pool leak bucket test, step by step
One bucket and two marks tell you whether a pool is leaking or just losing water to the sun. Run it and read the outcome.
Reasons for a high water bill
Eight reasons the bill climbs, from a silent toilet leak to an irrigation valve stuck open, each with a way to check.
Need a device tested?
Phone the line to arrange service. Someone on the line can hand you to a contractor who handles backflow work.