Misconceptions and misunderstandings in agricultural water management: time for revisiting, reflection and rethinking

Over the past years, several concepts in water management have emerged and were further developed. They included approaches for saving water and improving water use efficiency and productivity, sustainable water management strategies, salinity control, remote sensing applications to estimate crop evapotranspiration (ETc), soil moisture, crop yield and land cover, using models as water management tools and for designing reservoirs and dams. The intention was great, but the application of the concepts did not always match the intention. Examples of misunderstandings and misconceptions include incorrect application of deficit irrigation, using water use efficiency instead of water productivity, misunderstanding the water accounting system elements, misuse of the term sustainability, leaching with every irrigation, using the term upscaling instead of aggregation, incorrect use of long-term average flow for designing dams and reservoirs, believing that remote sensing data are direct measurements for ETc or soil moisture and believing that well-calibrated/validated models do not have inaccuracy and uncertainty in their results. This paper highlights these concepts and their misuse and misunderstandings as well as explains the true meaning and application of each concept. The paper also explains why concepts were misunderstood and suggests approaches to improve the understanding and accurate application of the concepts. This paper is based on a presentation of the International Commission on Irrigation and Drainage (ICID) President in the 74th International Executive Council Meeting of ICID in Visakhapatnam, India, 4 November 2023.