Water Requirements of Wheat Crops in a Small Watershed by Using CROPWAT

A study was conducted to determine the water demand of wheat crops in the area around the Tonna Pumping Canal. It used 2017-2018 climate data to determine the need for wheat crops in water in CROPWAT. Reference crop evapotranspiration (ETo) was determined using the FAO Penman Monteith method. When considering wheat crops, four stages of crop growth were considered: early stage, development stage, mid-maturity, and late-maturity stages. Crops were planted in the 2017 rabi season and yields were determined for each.This study shows that baseline evapotranspiration (ETo) in the study area ranges from 1.48 to 3.98 mm/day. Crop evapotranspiration (ETc) and water demand for wheat crops ranged from 0.44 to 3.75 mm/day and 1.9 to 39.8 mm/day. The maximum water demand was 0.13 l/s/ha or 1.1 mm/day with 65% efficiency. The irrigation water demand was estimated at about 27.93 mm/day, and the actual water intake was 81,000.29 m3. The canal can therefore provide a convenient supply of the water needed to irrigate the area.