Water at one low head for a few minutes
After a zone shuts off, the water left in its pipe drains out of the lowest head. If it stops after a few minutes, that’s drainage, not a leak. A head with a built-in check valve, or a check valve added under it, usually fixes it.
Water seeping at a head all the time
If a head at the low end of a zone keeps weeping long after the zone is off, the valve for that zone is probably letting a little water through. Debris or a worn diaphragm is the usual cause. See how to fix a sprinkler valve.
A valve box that keeps filling with water
Bail or pump the box out and watch where the water comes back from. Water bubbling from the valve body, the bonnet, or a fitting points to the valve or the manifold. Water coming in from the side of the box, with clean water, often means a leak on the main line nearby. Muddy water that only shows up after watering or rain is often groundwater or runoff.
To tell if water is moving through the system with everything off, look at the water meter with all indoor and outdoor water turned off. If the meter’s leak indicator still moves, there’s a leak somewhere, though not always in the irrigation.
Why it matters here
The main line to your valves stays under pressure all the time, so a leak there runs day and night. In Madera, water running into the gutter can bring a citation that has to be fixed within five days (City of Madera). In Fresno and Clovis, water on the sidewalk or street is the kind of waste the cities ask residents to avoid. Before digging, call 811.
We find and fix valve and main line leaks in Fresno, Clovis, Madera, and Madera Ranchos.
Safety first: if you can’t stop the water, close the shutoff valve for the irrigation system, or the main shutoff to the house. Before you dig anywhere, call 811 to have buried utility lines marked.
Written by ACRE Landscape Co., Fresno & Clovis. Updated October 26, 2026.