Utah Surface Irrigation Water Optimization Opportunities and Barriers Matt Yost, Clara Anderson, Burdette Barker, Justin Clawson, Kalen Taylor, and Michael Pace
Introduction Surface irrigation is the oldest form of irrigation and can be practiced in many forms (e.g., basin, border, furrow, graded furrow, wild flood) and is known by many terms (e.g., gravity, flood). Surface irrigation systems are increasingly being replaced with pressurized irrigation systems. Since 1970, land irrigated using surface irrigation in Utah has decreased from over 750,000 acres to around 500,000 (Barker et al., 2023). The trends in Utah are similar to those in several other states in the West. The reasons for this change vary, but the primary drivers are the diminishing availability and increasing costs of farm labor. Pressurized systems can significantly reduce farm labor and, in some cases, can improve irrigation uniformity and crop yield. Furthermore, surface irrigation is sometimes considered less water efficient than pressurized systems (Rajwade et al., 2018), which often leads to more economic incentives, tax breaks, and government support for pressurized systems. However, surface systems often have less consumptive water use than pressurized systems and provide many unique benefits to irrigators (e.g., salinity control, rodent control, beneficial runoff) and the environment (e.g., groundwater recharge, wildlife habitat) (Crookston et al.,
Highlights • • • •
A Utah State University (USU) survey of 126 surface irrigators showed diverse farm sizes and management practices, with most irrigators relying on traditional methods like open ditches. Most farmers schedule irrigation based on soil feel and crop condition or a schedule set by the water supplier or cropping practices, with fewer using more advanced tools like soil moisture sensors or evapotranspiration data. Precision land leveling was the most common optimization practice (27%), but high costs, fear of reduced yields, and lack of information remain major barriers to adoption of this and other optimization practices in surface irrigation. Many producers rely on neighboring farmers and university Extension services for guidance. Costsharing programs and accessible education are key to increasing conservation efforts. 1