Optimization of Logung Reservoir Performance

Logung Reservoir is located in the Logung River and Gajah River. The upstream is in the Muria Mountains. The main dam of Logung Reservoir is in Tanjungrejo Village, Jekulo Sub-District, Kudus Regency, Central Java. The main purpose of Logung Reservoir in addition to being a flood control infrastructure is to meet the water needs of Logung Irrigation Area of 2.805 Ha and to fulfill the raw water of 200 liters/second for the people of Jekulo and Dawe Districts. This research is intended to obtain the most optimal operation pattern of the reservoir through a reservoir release formula using the Implicitly Stochastic Dynamic Programming method through a more effective and more reliable release policy. The reservoir release formula was then simulated to meet the needs during the 25 year operating period. From the results of optimization and simulation modelling, it showed that the reliability level of reservoirs in meeting irrigation and raw water needs is 80,33%, reservoir resilience is 52,54% and reservoir vulnerability throughout the simulation period is 52,51 million m³.