Logistics of irrigation pump shut off and well-switching for a groundwater-based maize–rice–soybean farm in Northeast Arkansas

Irrigation seasons are hectic in the Mississippi Alluvial Plain (MAP) where the majority of approximately four million hectares of soybean, rice, maize, cotton, and peanut are irrigated using over 80,000 groundwater wells. With farmer input, this study simulated the 2021 irrigation season for a farm that uses 43 groundwater wells to irrigate approximately 1100 ha row crops. This was done to estimate the numbers and timings of two key well operations: switching a well from one field to another and shutting off an irrigation pump once an irrigation cycle is completed. The distances driven to operate these wells throughout the 91-day season and excess pumping associated with delayed pump shut off were also estimated. Results suggest that the farmers drove approximately 9900 km to perform 780 well operations comprised of 398 well-switching and 382 pump shut off tasks. About 3000 km (37 %) were driven to completely shut off the irrigation pumps once the irrigation events were complete. About 190 pump shut off operations occurred between 1900 and 0700 h when the farmers were “off-duty,” resulting in excess pumping equivalent to ≈ 7 % of total pumping (40,892 h), corresponding to about 396,000 m 3 irrigation water. Three working equations, determined a priori as a check for the well operation estimates, will be useful when evaluating the economics and labor savings of remote irrigation pump shut off and other automated tasks such as well-switching. • An estimated 780 well operations were performed to irrigate 1100 ha row crops. • 398 were for well-switching between fields and 382 for irrigation pump shut off. • About 3000 km (37 % of total driving) were driven to shut off the irrigation pumps. • 7–9 % of seasonal irrigation pumping was attributed to delayed pump shut off. • Equations for the number of well switching and pump shut off tasks were developed.