Center pivot irrigation systems are designed and managed to apply water as uniformly as possible to enhance crop production. Uniformity has a direct effect on the system’s overall application efficiency, which is a measure of how well an irrigation system delivers water to a crop’s root zone.
Research has shown that concentrations of nitrate - nitrogen have accumulated in the groundwater beneath areas where irrigation is intense and where the soils are permeable allowing for leaching of nitrogen fertilizer. Leaching is most severe for surface irrigation systems used to irrigate sandy soils. The Platte River Valley and Eastern Sandhills have been most severely affected.
Advantages and Disadvantages of Subsurface Drip Irrigation, EC776 (PDF, 1.2 MB; 8 full color pages) Discusses subsurface drip irrigation, including the advantages of water application efficiency and savings, energy savings and potential yield increases and the disadvantges of initial investment, system capacity, design restrictions and emitter clogging.