How Do I Detect a Leak in My Sprinkler System?

The short answer

Start with the Water Meter

Turn off all sprinklers and make sure no other water is running inside or outside your home. Note the reading on your water meter, then wait about half an hour without using any water. If the meter moves, water is escaping somewhere in your system.

A slow leak may show only a small change, so check the meter again after an hour. If the meter does not move, the leak is likely not in the supply line. If it does move, you know you have a leak and can begin looking for the source.

Look for Visible Signs

Walk your yard and look for areas where the grass is greener or grows faster than the rest. Soggy or muddy spots, especially days after watering, often point to a leak. Also check for standing water near sprinkler heads or along pipe trenches.

Inspect each sprinkler head for cracks, missing parts, or water pooling around the base. Look at the valves and connections for drips or corrosion. A hissing sound near a valve or head can also indicate a leak that is not yet visible.

Unusually lush grass patches
Soggy or muddy soil days after watering
Cracked or broken sprinkler heads
Water pooling near valves or connections
Low water pressure during operation
Hissing sounds near pipes or heads

Check Pressure and Flow

Turn on one zone at a time and watch how the sprinklers perform. If some heads spray weakly or not at all, you may have a leak or a blockage in that zone. Uneven spray patterns can also signal a problem in the line.

A leak can reduce water pressure across the whole system. If you notice a sudden drop in pressure, check the meter again and inspect the most likely trouble spots, such as joints and elbows. If the issue persists, a moisture mapping service can help locate hidden leaks without digging up your yard.

Inspect the Backflow and Shutoff Valve

Your sprinkler system has a backflow preventer and a shutoff valve, usually near the main water line. Check these for leaks, especially after winter or during dry seasons. A small drip here can waste a lot of water over time.

If you live in Redmond, keep the location of your shutoff valve written down so you can turn off the water quickly if a leak is found. Knowing how to shut off the system can prevent further damage while you arrange for repairs.

When to Call in the Pros

If you cannot find the leak or it is under a slab, driveway, or in a wall, the pros can help. They use specialized tools to detect leaks without tearing up your yard. A water damage inspection can reveal the exact location and the extent of any moisture damage.

If a leak has already caused water damage to your home, such as soaked drywall or subflooring, the pros can handle extraction and drying. Related services like leak detection and cleanup can address the problem from start to finish, reducing the risk of mold and structural issues.

Frequently asked questions

How do I know if my sprinkler leak is underground?

Look for soggy or unusually green patches along the line, even when you have not watered recently. You may also hear a hissing sound or notice a drop in water pressure. If the leak is under a slab or driveway, the pros can use moisture mapping to locate it.

Can a small sprinkler leak cause water damage to my home?

Yes, even a small leak can saturate soil and seep into your foundation, basement, or crawlspace. Over time, this can damage drywall, subflooring, and promote mold growth. If you suspect a leak near your house, act quickly to find and fix it.

Should I turn off my sprinkler system if I suspect a leak?

Yes, turning off the system at the shutoff valve can stop the water flow and prevent further damage. This is a good first step while you investigate. If the leak is significant, the pros can help with extraction and drying to protect your home.