Date of this Version
University of Nebraska Extension Circular EC3017. Lincoln, NE. 2017.
Center pivot irrigation has been the most rapidly expanding form of irrigation in the Central Great Plains and across the United States. The amount of land irrigated with sprinkler, gravity and drip or trickle systems was determined for all states in the USA in the Farm and Ranch Irrigation Survey1 by the USDA in 2012. Results of the survey for the Great Plains States shows that approximately 85% of the land in Nebraska is irrigated with center pivots and that very little land was irrigated with drip systems in 2012 (Figure 1). The percentage of land irrigated with sprinklers in neighboring states was similar to the percentage in Nebraska. Results for Colorado, New Mexico and Wyoming include irrigation from the western slopes of the Rocky Mountains where large surface water projects provide water to farms for gravity irrigation. The percentage of land irrigated with sprinklers is similar to that for Nebraska on the eastern plains of Colorado, New Mexico and Wyoming. Virtually all sprinkler-irrigated land in the Great Plains is by center pivots.
With widespread use of pivots, it is important to provide techniques to evaluate if pivots are operating as designed and to develop methods to identify issues in producer fields. In this document, we describe the design procedure for center pivots to illustrate how pivots should operate and discuss issues in center pivot performance that we are observing in producer fields. We also present procedures for selecting sprinkler packages and a checklist of things that can help ensure that the system is operating efficiently.