L euwikeris Reservoir is one of the reservoirs in West JavaProvince. This reservoir operation pattern method uses a storage simulation. Inthis operating pattern simulation, it used the inflow data which contains of therainfall data and the discharge data, meanwhile the outflow data used thesecondary data including the raw water data, the irrigation water needs, theevaporation data, the river maintenance data, dan the curved reservoir capacitydata. Simulation of this reservoir operation pattern results in three conditions ofthe boundary year, namely wet years (35%), normal years (50%), and dry years(65%). This reservoir is used for raw water needs, irrigation water needs,evaporation, river maintenance, and PLTA needs. Leuwikeris Reservoir isexpected to provide raw water requirements of 0.875 m3 / sec, irrigate an area of19.733 Ha, and prodece 20 MW of hydropower.