When installing a permanent irrigation system in the garden, underground sprinklers make the most sense. Not only are big, clunky tubes kept out of footpaths, but the hoses are also safe from the sharp blades of your lawnmower. But freezing temperatures and roots can cause damage to the underground line. Locating an underground leak can be difficult, but there are a plethora of leak detectors available on the market that make it easier to find underground leaks.
Inspect the yard for any signs of sinking or large, mushy wet patches. This is the location of your leak. Look for patches where your plants are greener than in other places. If no visible signs are apparent, you will need a portable electronic leak detector.
Place the ground piece on the ground and insert the headphones into your ears.
Turn the device on and listen for the leak. You will hear a rumbling noise in the headphones as you get close to the leak.