The Nebraska Center-Pivot Inventory: An Example of Operational Satellite Remote Sensing on a Long-Term Basis

The objective of this paper is to summarize the history, procedures, and results of a long-term program of inventorying center-pivot irrigation systems in Nebraska. Data concerning the location of pivots have been collected each year from 1972 to the present, and summarized annually as a map publication. Inventory procedures are simplistic, consisting of identifying and mapping occurrences of the characteristically circular pivot systems as interpreted from photographic enlargements of Landsat imagery. A total of 2,665 pivots were recorded in 1972, and the cumulative total for 1986 was 26,208; nearly a ten-fold increase over 14 years. The temporal periods of greatest increase coincide, as one would expect, with generally dry conditions in the state. While the method for remote detection of irrigation systems is ordinary, we believe that the Nebraska center-pivot inventory provides an excellent example of the practical utility of remote sensing.