Annual test, report filed
Backflow testing for Houston sprinklers and businesses
If a letter from the water department says your backflow assembly is due, or a new irrigation system needs its first test, the job is short. We test the device with gauges, fix it if it fails, and send the results in.
- We answer 24/7 to set up a test
- Testing from our South Belt base by Ellington
- Each check valve and relief valve tested with a gauge kit
Updated October 2026
Short answer
Backflow testing in Houston is required at installation, after any repair or move, and every year after that, under state rules and the City of Houston Plumbing Code. We connect a differential gauge kit to the test cocks, check each valve against its required reading, and give you the results on the form the water department asks for.
The job
What a backflow test actually checks
A backflow assembly keeps water from your property, such as sprinkler water sitting in the yard or process water in a business, from being pulled back into the public supply when pressure drops. Inside are spring-loaded check valves and, on some assemblies, a relief valve. Over a year, debris, mineral scale and worn rubber can keep those parts from closing tight.
A test puts a number on each part. We close the shut-offs in order, read the pressure difference across each check, and confirm the relief valve opens at the right point. A pass means the assembly is holding. A fail means a part is not closing, and the device needs repair before it can pass a retest. Testing applies to an existing device; if you need a new one, see backflow preventer installation.
Scope of the work
What comes with a backflow test visit
- Locating and clearing access to the assembly
- Recording the make, model, size and serial number
- Gauge readings on each check valve
- Relief valve opening point on RPZ assemblies
- Air inlet check on pressure vacuum breakers
- Water restored and the device left in service
- Completed test report for your records
- Repair quote if the assembly fails
The versions we see most
Irrigation backflow tests
Most homes with an in-ground sprinkler system have a backflow assembly on the irrigation line, often a pressure vacuum breaker near the front of the house or a double check in a ground box. The test takes well under an hour. We shut the irrigation supply, connect the gauge kit, read the check valve and air inlet, and turn the system back on. If the device sits under a shrub or a box full of dirt, we clear around it first. Your house water stays on throughout.
Commercial assembly testing
Restaurants, offices, apartments and car washes often have one or more larger assemblies, typically reduced pressure zone devices on the domestic line or double checks on fire and irrigation lines. Testing a domestic RPZ briefly interrupts water to the building, so we schedule around open hours and let you know how long the shut-off will last. Each assembly gets its own report with the serial number and location. If you manage several sites, we can line up the tests on one route. Our commercial plumbing page covers the rest of the building.
Failed test repairs
A failed test usually traces to a check valve that will not seal because of debris, a torn rubber disc, a weak spring or scale on the seat. Many assemblies can be rebuilt in place with a repair kit: we isolate the device, open the bodies, clean or replace the internals and test again. If parts are no longer made for an older model, or the body itself is cracked, replacing the assembly is the realistic option. Either way you get a passing report once the device holds.
Local to southeast Houston
The Houston rule behind the yearly test
State rules and the City of Houston Plumbing Code call for backflow preventer assemblies to be tested when they are installed, when they are repaired or relocated, and annually after that. That is why the reminder arrives every year even when nothing has changed. The yearly date usually follows the last passing test. If you have bought a property with sprinklers or a commercial line and never had a test, it is worth checking with your water provider before the next notice arrives.
Step by step
A backflow test from arrival to report
Find the assembly
We locate the device, clear the box and note the make, size and serial number.
Hook up the gauges
The test kit connects to the test cocks and the shut-offs are closed in order.
Read each valve
Check valves and relief valve readings are recorded against required values.
Restore water
Valves reopen and the line goes back into normal service.
File the results
You get the completed report, and we send it where the water department asks.
Talk to a plumber now
Any hour, any day. Tell us what you see.
Pricing
What affects the cost of a backflow test
A routine test is a short visit. The price moves with the number and type of assemblies and whether anything needs repair.
Type of assembly
An RPZ has more parts to test than a pressure vacuum breaker.
Number of devices
Properties with several assemblies need a test and a report for each one.
Access
Buried boxes, cages and rooftop devices take longer to reach.
Repairs after a fail
Rebuild kits and a retest add to the visit.
Shut-off timing
Commercial tests scheduled after hours can take more planning.
Typical planning range: $30 - $300 per device for backflow testing, per HomeGuide (Sept). That is a published range, not a quote. Your price comes after we look.
Timing
How long a backflow test takes
A single irrigation device usually takes 20 to 45 minutes, including finding and clearing the box. Commercial RPZ assemblies take a bit longer, and building water is off only while that device is being tested. If a device fails and the parts are on hand, a rebuild and retest often add an hour or two to the same visit.
Common questions
Backflow Testing questions from Houston homeowners
In Houston, at installation, after any repair or relocation, and then every year. Many water providers send a reminder when the annual test is coming due.
The device needs to be repaired or replaced and then retested. Often we can rebuild it with a kit on the same visit, so you get a passing report without a second trip.
For an irrigation device, only the sprinkler line is off. For a commercial assembly on the main domestic line, building water is off briefly while that device is tested.
Not usually for an outdoor sprinkler device, as long as we can reach it and the gate is open. For a business, someone should be on site to know when water will be off.
You receive a copy, and we send the report to the water department or provider that requested it, in the format they ask for.
Same system, different job
Related plumbing services
- Backflow Preventer InstallationNew or replacement backflow assemblies for sprinklers, fire lines and businesses.
- Commercial PlumbingRestrooms, kitchens and tenant spaces kept running for businesses and landlords.
- Outdoor Faucet RepairLeaking hose bibs and frozen spigots repaired or swapped for frost-free valves.
Not sure it is time yet?
Call and describe the setup. We will tell you plainly whether it can wait.