IRRIGATION WATER MANAGEMENT

Gravity Flow Systems—many irrigation systems rely on gravity to distribute water across the field. Land treatments—such as soil borders and furrows—are used to control lateral water movement and to channel water flow down the field. Gravity systems are best suited to medium- and fine-textured soils with higher moisture- holding capacities; field slope should be minimal and fairly uniform to permit controlled advance of water.

Pressurized Systems — including sprinkler and low-flow irrigation systems—use pressure to distribute water. With rare exceptions, the pressure to distribute water results from using pumps, which requires energy. With sprinkler systems water is sprayed over the field surface, usually from above-ground piping. Sprinklers may be operated on moderately sloping or rolling terrain unsuited to gravity systems, and are well suited to coarser soils with higher water infiltration.

Low-flow irrigation systems— including drip, trickle, and micro-sprinklers—use small-diameter tubes placed above or below the field’s surface. Frequent, slow applications of water are applied to soil through small holes or emitters. Water is dispensed directly to the root zone, reducing runoff or deep percolation and minimizing evaporation. Pressurized systems, while more flexible in meeting crop water demands, require more energy and higher investment costs.