Inaccurate water release has occurred from Gunungrowo Reservoir. In May–June, there is excess water release from Gunungrowo Reservoir while in the period from July to August there is a shortage of water release. Therefore the reservoir operation should be evaluated and updated in order to obtain optimal results and to adjust the changes. The purpose of this study was to evaluate the existing reservoir operation and to carry out an optimization to find the optimal reservoir operation. The objective is to conduct hydrological analysis, evaluate the reservoir operation, formulate a model of reservoir operation, optimize the reservoir operation, and analyse the results of reservoir operation optimization. Optimization of reservoir operation generates the water level of reservoirs and the release of water in each period as well as the objective function value under each scenario of reservoir operation. The existing reservoir operation is not optimal and has a reliability of only 24%. In the operation of the existing reservoir, emptying of the reservoir storage always happens and inaccuracies in the release of water have occurred. The optimal reservoir operation is scenario I, with a reliability of 75%, in which water is released in Planting Season II and Planting Season III.
Multiobjective Reservoir Operation Optimization Using Improved Multiobjective Dynamic Programming Based on Reference Lines