A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering, School of Engineering and Technology

Thesis (M.Eng.) - Asian Institute of Technology, 1991

The operation of the Jagdishpur reservoir and the main canal of the Banganga Irrigation Project in Nepal has been practised so far in an ad-hoc basis and as a result there is a recurrent shortage of water especially at the tail end portion of the command area. A Simulation model has been developed with deterministic crop water demand and stochastic inflow for the conjunctive operation of the diversion canal and the reservoir system. Synthetic flows for 50 years have been generated from the available short historical inflow records to find the decadewise release policy and the reliability of the system. Out of several alternatives tested in the simulation runs by varying the main canal capacity (off-taking from reservoir) and the reservoir capacity, the optimal set of alternatives have been identified by using compromise programming. From the simulation results, we find that the reliability is lower when the command area is high and vice-versa as expected. The model developed has been used for the case study of the above mentioned irrigation project in Western Nepal. The standard operating rule developed and the non-dominated set of alternatives if applied to this project would help in improving the reliability and the performance of the system. From the study, it is found that the existing reservoir capacity is 50% lower and the main canal capacity is 10% lower than required for acceptable irrigation reliability.