If you suspect that you have a line break in your irrigation system, you’ll need to locate the exact pipe that is broken in order to repair it. First, determine whether the line break is in a main “constant pressure” line or a lateral “zone” line. The main line is the pipe that delivers pressurized water from the main water source to the lateral zone lines. If you have a break in the main line, you’ll see water leaking and pooling in large quantities, even when the system is turned off. If you have a break in a lateral line, the leaking water will surface and pool only when the system is turned on.
Troubleshooting the Irrigation Line Break
Shut off the water completely if you have a main line break. Or turn off the water flow to the affected zone if you have a lateral line break.
Dig a hole into the ground using a spade or shovel to remove sod and soil from the area where the water is pooling. Determine what kind of pipe is broken, such as a PVC pipe or a smaller, flexible polyethylene pipe.
Dig and remove the soil around the pipe. If your line break is in a poly pipe that is usually used for lateral lines, expose 1 to 2 feet of the pipe length and remove 2 to 3 inches of soil on either side of the pipe section. For a PVC pipe, which is usually used for main lines, expose at least 2 feet of the pipe length and 6 inches on either side of the pipe.
Inspect the pipe damage to determine what caused the line break. Possible causes include frost and frozen water damage, cracks or holes caused by lawn aerators or other equipment, damage from deep-growing roots, bad installation or defective pipes and fittings, or punctures from digging animals.
Purchase a new length of PVC or poly pipe, at least two new fittings and any other materials that need replacing, such as sprinkler heads. Select the correct fitting and pipe sizes that match your existing system.
Replacing a Poly Pipe for a Lateral Line
Replace a broken poly pipe with a barbed fitting. Measure the new fitting.
Measure a length of the damaged pipe that is the same length as the new fitting and mark the measurements on the broken pipe. Try to ensure that the damaged area is in the center.
Cut the damaged section of pipe using pipe cutters, following your measurement marks. Thread the barbed ends of the new fitting pipe into the cut ends of the lateral line.
Place a pipe clamp on either end of the fitting and crimp the connections closed.
Replacing a PVC Pipe
Cut and remove the damaged section of PVC pipe using pipe cutters. Cut the pipe at least 2 or 3 inches beyond the damaged area on either end of the pipe.
Remove any pooled water from around the PVC pipe. Dry and wipe the cut ends of the piping clean using a rag.
Insert one end of the telescoping repair coupling to one of the cut ends of PVC pipe to test the fit, which should be snug. Remove the repair coupling and apply cement glue to the outside of the repair coupling’s ends and inside of the PVC pipe’s cut ends.
Insert one end of the telescoping repair coupling to one cut end of the PVC pipe. Extend the repair coupling to the other cut end of the PVC pipe and insert it. Allow the glue to dry and set before testing the system.