Irrigation Systems

Irrigation methods are classified into surface irrigation, sprinkler irrigation, and localized irrigation (drip/micro irrigation). Surface irrigation uses gravity: the water is distributed over the field as it infiltrates. With sprinkler irrigation, water is distributed across the field using pressurized pipes and sprinkled over the soil through nozzles. Drip/micro-irrigation systems are conceived to localize the water to parts of the field and apply it frequently. The factors to be considered when selecting an irrigation method are project goals (maximizing economic return, minimizing investment cost, conserving water, and water quality), institutional and social site conditions (financial, labor availability, durability, and robustness), and physical site conditions (soil and topography).