Root infiltration is the most common cause for a plug in the line. Flood irrigation pipe is made of concrete of which were generally built in 3’ sections. This means every 3’ we have a pipe connecting to one another with a “joint”. The joint is sealed with concrete or mortar mix. As the pipes ages, air pressure + water pressure + use cause these connections to fail. The result is a cracked joint. The cracked joint can allow roots to easily penetrate the system. This allows the roots to grow very quickly as there is a constant supply of water. It does not always take a broken joint to allow roots to infiltrate. Any small fracture in the pipe will “sweat” moisture to the surface. Roots will follow the source of the moisture.
Sediment build up and rock build are also common towards the lower portions of a delivery system. We can hydro jet (water saw/jet) roots or debris out of the line. In some cases we need to remove the plug by hand. This means excavate the pipe, cut it open, remove the plug and repair the pipe.