How often should you test a sprinkler system?
Updated July 2026
Run a full startup on an in-ground sprinkler system once every spring and cycle through each zone to check coverage, clogged heads, and leaks, then spot-check the zones monthly through the watering season. Winter frost heave, mowers, and rodents shift and crack heads over the off months, so the first run of the year is where you catch the damage. A broken head or a buried leak wastes water and money silently, leaving one corner soaked and eroded while another stays dry and brown.
What changes the interval
| Your situation | Interval | Why |
|---|---|---|
| Full system startup | Once a year, spring | Frost heave and off-season damage show up the moment the water is back on |
| Each zone run-through | Monthly in season | Heads clog, tilt, and get clipped by the mower between cycles |
| Backflow preventer test | Yearly (often legally required) | A failed valve can siphon lawn water back into the drinking supply |
| Controller and backup battery | Spring and after outages | A dead backup battery wipes the whole watering program after a power blip |
| Rain or soil sensor | Twice a year | A stuck sensor either wastes water in rain or skips cycles the lawn needs |
| Drip and micro-spray zones | Monthly | Clogged emitters starve beds while you assume they are being watered |
| Fall winterization | Every fall in freeze climates | Water left in the lines splits pipes and manifolds over winter |
The cost of skipping it
What skipping it costs: a single spray head snapped off at the base can gush hundreds of gallons in one 20-minute cycle, quietly padding the water bill while the far end of that zone stays brown. A head is a $5–15 part to swap yourself, or a $75–150 service call; a cracked lateral line under pressure erodes beds and undermines walkways, and a mainline break runs $300–800. Skipping the fall blow-out is worse still: freeze-split pipes and manifolds cost $500–1,500 to dig up and repair. A properly tested system lasts 20–40 years.
How to do it (30–45 minutes · DIY spring startup)
- Before the first run, walk the yard and clear grass and mud off every head, and check the controller date and its backup battery.
- Open the main supply valve slowly to fill the lines gently; snapping it open water-hammers the fittings and cracks them.
- Run each zone from the controller for a full cycle and watch that every head pops up fully, sprays evenly, and retracts.
- Flag any head that mists (pressure too high), dribbles (clogged nozzle), or leaks at the base, then clean or replace it.
- Look for low spots that stay wet after a cycle, a sign of a buried leak, and reset the seasonal schedule to match the weather.
Knowing the interval is the easy half. OnOtto reminds you at the right interval, and it won't let you snooze it into next year. Tasks persist until they're done, and completing sprinkler tests schedules the next one automatically.
Put this on autopilot, free for 30 daysFrequently asked questions
Why are my sprinkler heads not popping up?
The usual culprits, in order: low water pressure at the source, a nozzle clogged with grit, a broken lateral line bleeding pressure before it reaches the head, or simply too many heads crowded onto one zone. Start by cleaning the filter screen under the nozzle, then check whether nearby heads in the same zone are weak too, which points to a pressure or line problem rather than one bad head. Our guide to sprinkler heads that will not pop up walks through each fix.
Do I really need to winterize the system?
If your ground freezes, absolutely. Water left in the lines and backflow valve expands as it freezes and splits pipes, fittings, and the manifold, and you will not know until spring startup floods the yard. A professional compressed-air blow-out runs $75–150, cheap insurance against a $500–1,500 freeze repair. See exactly what is at stake in skipping sprinkler winterization.
How much water can one broken head actually waste?
More than people expect. A head snapped off at the riser has no nozzle to throttle flow, so it runs wide open every time the zone fires, often hundreds of gallons per cycle. Run three cycles a week and a single broken head can add thousands of gallons a month to your bill, all of it pooling in one spot instead of watering the lawn. That is why the monthly zone-by-zone glance pays for itself, you catch the geyser before a full billing cycle does.
What is a backflow test and why is it required?
The backflow preventer is the valve that stops irrigation water, along with any fertilizer or pesticide it has touched, from being siphoned back into your home's drinking water if pressure drops. Because that is a public-health risk, many municipalities require a certified annual test, typically $75–150, and will send a reminder notice. A failed test means repairing or replacing the assembly before the system can legally run.