Glossary of Irrigation Terms

HDPE is high-density polyethylene, a polymer made from petroleum. It's extremely versatile, durable and flexible. Its properties make it very useful for large irrigation projects where its flexibility can cope with sharper bending radii for example and the kind of fluctuations in pressure, movement and external factors like UV rays and heat or cold, more easily than PVC. Because the joints are heat-fused, they are extremely strong and are more likely to create a leak-free system.

The amount of water pressure lost as water travels through an irrigation system. The head loss of a specific system can be divided into major head loss; caused by friction in the pipes themselves, and minor head loss; caused by components such as vales, backflow preventers, bends and tees.

An irrigation zone hydraulic valve is a type of control valve. Water is fed under pressure through small hydraulic control tubes to actuate a signal from the controller to the valve.