Mainline, valve or zone
| Where | When it leaks | What you notice |
|---|---|---|
| Mainline (house to valves) | All the time | Meter moves with the system off; one soggy spot that never dries |
| Zone valve | All the time, through one zone | Water trickling from the lowest heads of one zone, wet valve box |
| Zone lateral | Only when that zone runs | Weak heads, geysers or bubbling soil in one zone |
| Backflow preventer | All the time once it fails | Dripping or spraying near the house, often after a freeze |
Five checks you can do
- Meter with the system offIf it moves, close the irrigation shutoff. If it stops, the mainline, a valve or the backflow device is leaking.
- Separate irrigation meterIf your home has one, watch it with the controller off. Any movement is a sprinkler leak.
- Run zones one at a timeWalk each zone looking for weak heads, geysers and soggy spots.
- Open the valve boxesStanding water or a hissing valve points to a valve that isn’t sealing.
- Check the backflow preventerLook for drips or spray, especially in spring.
More detail: how to find a sprinkler leak.
Think you have a leak? Call and tell us what you’re noticing in your Center Grove home.
(877) 729-0265How we pinpoint it
Isolate
Meter and valve tests separate the irrigation system from the house, then the mainline from the zones.
Locate the pipe
Mainlines and laterals are traced, since they rarely run where the heads suggest.
Listen or use gas
Acoustic listening on the pressurized mainline; tracer gas for quiet leaks in plastic pipe.
Repair
The break, valve or fitting is fixed through one small hole and the zone is tested.
Backflow testing and winterizing
Indiana rules (327 IAC 8-10) require testable backflow prevention devices to be tested every year by a state-certified tester. Your utility, Indiana American Water or the Town of Bargersville, can tell you how results are reported. A device that fails its test is also a common leak.
Before the first hard freeze, the system should be shut off and blown out with compressed air. Water left in the backflow device and shallow lines is behind most spring sprinkler leaks.
Sprinkler leak or something else?
If the meter keeps moving after you close the irrigation shutoff, the leak isn’t in the sprinklers. Close the house main next: if the meter stops, see slab leak detection in Center Grove; if it keeps moving, see water line leak detection in Center Grove. If you have a pool, its auto-fill can also be the cause; see pool leak detection in Center Grove.
Sprinkler Leak Detection & Repair: questions from Center Grove homeowners
Why is my water bill so high in summer?
In Center Grove, the sprinkler system is the most common cause, followed by a pool auto-fill. A valve that doesn’t close or a mainline leak wastes water all day, even when the system isn’t running.
One zone keeps running after it shuts off. What is it?
Usually a valve that isn’t sealing, from debris or a worn diaphragm. Water drains out the lowest heads of that zone. The valve can be cleaned or replaced.
Does Indiana require backflow testing?
Yes. Indiana rules (327 IAC 8-10) require testable backflow prevention devices to be tested annually by a state-certified tester.
Do you repair sprinkler leaks too?
Yes. Once the leak is marked, the pipe, fitting or valve is repaired through a small hole and the zone is tested.
Guides that go deeper
Sources: Indiana American Water; Town of Bargersville Water Utility; Indiana 811; Indiana Administrative Code, Title 327. Updated October 1, 2026.