How Irrigation Lines Work

Irrigation Line Problems and Repairs

Yard work can be rough on existing irrigation lines.
Yard work can be rough on existing irrigation lines.
Stephen Swintek/The Image Bank/Getty Images

Broken irrigation lines can cause a great deal of trouble. If water flows out through a busted segment of piping, plants in the immediate area can receive too much water while others go thirsty. Just a small leak can decrease water pressure and volume. If the water volume is high enough, a leak can even damage property and cause mudslides. Therefore, it's important to try to prevent irrigation line problems like breaks from happening and know how to repair them if they occur.

One simple factor to keep in mind is compacted soil. If you bury something underground, guess what happens when you drive a dump truck over the site? Vehicle, human and even pet traffic pushes down on the soil, compacting it and potentially crushing irrigation lines, unless the material is strong enough to withstand the pressure. Likewise, the photo illustrates what can happen when you carry out a little yard work and forget about subsurface irrigation lines. If the lines are located aboveground, your chances of damaging them with lawn and farming equipment may be even greater.

­Cold weather can pose another potential irrigation line problem. If water freezes (and therefore expands) inside your irrigation line, it can burst. To prevent this, some users make sure to flush most of the water out of lines during the winter. Also, the more flexible the material, the more it can withstand the expansion and contraction. For this reason, many landscapers prefer to use poly pipe in cooler regions and PVC in warmer climates.

Irrigation lines are like any other plumbing operation in that they can experience internal blockages. The key is to make sure the water flowing through the lines is properly filtered. Gray water irrigation systems are particularly prone to problems as the previously used water may contain bits of f­ood, hair or other debris. If these bits collect and build up inside the irrigation line, they can clog the pipe and block the system.

Animals can also pose a threat to irrigation lines -- and not just your loveably bored pet dogs and goats, either. Coyotes, gophers and various rodents often chew up poly pipe irrigation lines, mistaking them for food. Don't count out plants, either. If you think your subsurface yard irrigation system is set for life, nearby tree roots may give you a rather rude awakening over the years to come.

The task of repairing broken irrigation lines generally involves two steps: isolating the source of the break or breaks and either patching the break or replacing the segment of pipe or tubing. More advanced irrigation systems employ sensors to determine where flow pressure decreases, thus helping to isolate the point of the break. This technology is especially helpful with subsurface systems. When this isn't an option, farmers, landscapers and gardeners can always fall back on visual inspection. If the pipe is aboveground, you should be able to observe the leak while the water's running. If the pipe is underground, a particularly wet patch of soil above the leak often indicates the break. Then it's just a matter of shutting off the water, digging down and patching or replacing the segment of pipe.

Different irrigation line materials call for different forms of patching. A welding torch may work fine on a metal pipe, but you'll want to cement replacement lengths of PVC piping into place at the couplings and use clamps on poly pipes.

Explore the links below to learn even more about irrigation and lawn care.

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