Optimal Allocation of Canal Water for Conjunctive Use Planning

OPTALL model based on quadratic programming technique was employed to minimize the gap between water supply and irrigation requirement and optimal its well as equitable water allocation plan to meet the irrigation requirement computed after considering average, 75% dependable and actual rainfall for various distributaries of Patna Main Canal under Sone Canal system in India was developed. The optimal water allocation schedule was found much better than actual release because in no case supply - demand ratio was more than 1.0, whereas in case of actual release it was excessively higher than 1.0 in many distributaries of Patna Main Canal showing inequitable water distribution. In order to utilize canal water equitably, efficiently and judiciously, canal operation schedules need to be developed and reviewed in consultation with water users tinder various Situations of water availability. Through frequent meetings and dialogues between canal managers and water users and technical back stopping through such decision Support tools, most of the water conflicts can be resolved. The gap between optimal water release and irrigation requirement indicates that there is a need to promote ground water utilization and explore the possibility of conjunctive use of rain, surface and ground water in canal command to minimize the gap and improve the yield.