The planning and design of irrigation system is essential to supply the required amount of irrigation water. For effective scheduling of irrigation process proper knowledge on the water requirement of crops, water deficits and growth stages are needed. A study was conducted at the Singiripalyam distributory of Lower Bhavani Project(LBP) command in Tamilnadu forassesing the crop water requirement for multiple crops grown in area by using Aqua Crop 4.0 water productive model developed and modifed by FAO(2012). The reference crop evapotranspiration ETo was computed from the ETo calculator program developed by FAO. The average crop water requirement for the crops like Sugarcane, Banana, Paddy, Maize, Groundnut, Turmeric, Coconut and vegetables were estimated for the period 2004–2013. In this study Crop water requirement for normal, excess and deficit rainfall years were also computed by using the Aqua Crop 4.0 model. The highest crop water requirement was found to be for sugarcane (831mm) and the lowest for the Maize (319mm).
Water requirement, Reference Crop evapotranspiration(ETo), Effective rain fall
