The purpose of this study was to develop an optimum equipment model considering various objective functions and variables of agricultural reservoir. Traditional optimum function for feasibility assessment is based on economic benefit, but we tried new approach of feasibility assessment based on the number of beneficiary. The data of Yuraimi reservoir and Yongbong reservoir in Yesan-gun such as numbers of related people, construction costs, safe diagnosis have been gathered for applying developed model. Data are used for determining optimum strategy with restricted cost. For verifying results of optimum maintenance, real maintenance data of Yuraimi reservoir were compared with simulated strategy. Results show that simulated maintenance strategies are 3 times more effective than real maintenance data.