Many Fullerton tract homes from the 1950s through the 1970s were built before automatic sprinklers were common. Systems were added later by owners and landscapers, so the backflow device might be in a front planter, along a side yard, beside the house or in a box near the sidewalk.
Sprinkler heads sit at ground level, often in puddles after watering. If supply pressure drops, water touching soil, lawn chemicals and animal waste could be drawn back into the line. That is the hazard the irrigation backflow device addresses.
Devices you may find on a home irrigation line
| Device | Where it sits | Testable | Note |
|---|---|---|---|
| Pressure vacuum breaker (PVB) | Above ground, above the highest head it serves | Yes | The most common testable device on home irrigation |
| Double check assembly | Above ground or in a valve box | Yes | Used where a vacuum breaker cannot be placed high enough |
| RP assembly | Above ground with drainage below | Yes | Often required if fertilizer or chemicals are injected |
| Atmospheric vacuum breaker (AVB) | On each valve, above the heads | No | Cannot have a shutoff downstream; not testable |
Before the tester comes
- Locate the device and confirm it matches the notice.
- Trim shrubs and pull mulch back so the test cocks are reachable.
- Turn the irrigation controller off or to a rain delay for the visit.
- Note any zones that spray, leak or run weak.
- Check that the device is not buried, kinked or leaning.
- Have your controller location handy in case the tester needs to run a zone.
Spring start-up routine
Inspect the device
Look for cracks, missing caps and damage from mowers or edgers.
Open slowly
If the device has shutoffs that were closed, open them slowly to avoid a pressure surge.
Run each zone
Watch for spraying from the device and leaks at the heads.
Schedule the test
If a notice has arrived, book the test now rather than near the deadline.
Ask a tester or irrigation contractor
- Is the device installed at the right height above the highest sprinkler head?
- Is there a shutoff downstream of any atmospheric vacuum breaker?
- Would a different device type suit the yard better, and would the city accept it?
- Is the device protected from mower and foot traffic?
Common questions
Do drip systems need backflow protection too?
Drip and micro-irrigation lines connected to drinking water also need protection. Ask the water supplier what is required.
Can I move the device during a landscaping project?
Moving a required assembly may need approval and a new test. Check with the city before the landscaper starts.
What if my sprinkler system is no longer used?
Tell the water supplier. Any removal or permanent disconnection usually needs to be done and documented the way it requires.
General information for Fullerton, not a quote or professional advice. In an emergency, call 911.