Computerized Irrigation Systems

D.F. Heermann, G.W. Buchleiter, M.C. Blue, J.A. Chapman, and H.R. Duke




Irrigated agriculture constitutes only 15 percent of cropland in the U.S., but produces 41 percent of the total crop sales. About one third of the approximately 50 million irrigated acres are irrigated by center pivot sprinklers. These sprinklers are familiar to many air travelers as the huge green (or brown) circles. With such a large irrigated acreage, irrigation is a major user of water accounting for about 80% of total water use in the U.S. Overirrigation causes excessive leaching of nutrients and chemicals which degrade water quality. Irrigators as well as consumers are concerned that this water be managed wisely to conserve both its quantity and quality.

More than twenty years ago, this team began developing methodology to determine when to irrigate and how much water to apply with center pivot irrigation systems. They developed personal computer (PC) programs for use by irrigators to calculate crop water use from weather data. They developed a prototype computerized monitor and control system as a convenient means of controlling and monitoring irrigation systems to conserve water and energy. They have aggressively pursued transfer of irrigation water management technology, encouraging many other professionals to embrace the crop water use concepts, and worked with the industry to improve the computerized monitor and control systems. Now these technologies are used on an estimated ten percent of the center pivot irrigated land in the U.S., saving an estimated 160 billion gallons of water annually.