Precision Drone‑Derived Elevation Mapping Improves Irrigation Efficiency and Water Sustainability in Arkansas Row‑Crop Systems
Sustainable Agriculture and Natural Resources
Grant Beckwith
CEA-Agriculture
University of Arkansas Division of Agriculture
Stuttgart
Abstract
Furrow irrigation dominates Arkansas row-crop production, yet declining groundwater levels in the Mississippi Alluvial Aquifer are increasing pressure to improve irrigation efficiency. Small elevation differences across fields often contribute to non-uniform water advance, longer irrigation set times, runoff, and unnecessary pumping costs. Because elevation differences of only a few tenths of a foot can influence irrigation performance, precision elevation mapping provides a practical approach for identifying subtle topographic variation and improving irrigation management. Advances in RTK-enabled unmanned aerial systems (UAS) allow Extension personnel and producers to generate centimeter-level digital elevation models (DEMs) using RGB imagery and real-time kinematic positioning. Standardized workflows—including flight planning, automated image capture, photogrammetric processing, and elevation validation—produce high-resolution datasets that support irrigation design decisions. These datasets are used for land-grading verification, surge-valve layout, pipe-hole sizing, and identification of slope changes or drainage bottlenecks that may be overlooked with conventional survey methods. Field applications across Arkansas have demonstrated measurable improvements in irrigation performance when DEM-derived elevation data are incorporated into irrigation design. Producers using these recommendations have documented more uniform water advance, reduced irrigation set times, and reductions of 10–25 percent in applied irrigation water. These outcomes translate into sustainability indicators such as fewer acre-inches applied per acre, reduced gallons pumped per bushel, improved irrigation-efficiency ratings, and lower fuel or electricity use per irrigation event, reducing groundwater withdrawals from the Mississippi Alluvial Aquifer. Drone-derived elevation mapping supports the three pillars of agricultural sustainability. Environmentally, improved irrigation layout reduces runoff, sediment transport, nutrient loss, and groundwater withdrawals. Economically, increased efficiency lowers pumping costs, fuel use, and labor requirements while maintaining yield stability. Socially, conserving regional water resources strengthens the long-term viability of rural agricultural communities dependent on irrigation. This approach is transferable to other Mid-South and Delta regions with similar soils, topography, and irrigation challenges. Extension agents integrate UAS-derived elevation mapping into irrigation education through on-farm consultations, field demonstrations, workshops, and irrigation planning assistance. During 2024–2025, these efforts supported more than 40 producers and over 25,000 acres of row-crop land across Arkansas.
Authors: Grant Beckwith, Mike Hamilton
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Grant Beckwith CEA-Staff Chair / Agriculture, University of Arkansas Systems Division of Agriculture, Arkansas, 72160
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Mike Hamilton Irrigation Educator, University of Arkansas Systems Division of Agriculture, Arkansas, 72472