Agricultural Research Journal

Water conservation must be a priority in Indian agriculture, which is among the largest consumers of water globally. Farmers dependent on tank irrigation are increasingly facing challenges due to the loss of eco-friendly irrigation practices that rely on optimal crop water use. This study assessed crop water demand and supply to propose a net irrigation water scheme under two types of tank irrigation systems: non-system and system tanks, in the Chittoor and Srikakulam districts of Andhra Pradesh, India. Using the CROPWAT 8.0 software, irrigation water requirements were estimated based on primary data collected in 2021–22 and secondary data spanning 2001–2021. Under the non-system tank irrigation system, second-season paddy exhibited the highest irrigation water demand at 872.1 mm/ha during the rabi season, while groundnut had the lowest requirement at 57.4 mm/ha during kharif. On the other hand, in system tank irrigation, paddy required 266.7 mm/ha, while sugarcane demonstrated the highest water usage at 1046.7 mm/ha. The analysis of demand-supply gaps indicated that irrigation water availability was generally sufficient during agricultural growth phases, except in seasons marked by water deficits. Monthly net irrigation schemes in both tank-command areas were found to optimize crop growth and water distribution. The study highlights the need to reallocate water resources, particularly supplying rabi crops with kharif water through effective water harvesting techniques. These findings can guide farmers in determining appropriate crop water quantities and irrigation schedules in the study area and other regions with similar agro-climatic conditions.