A Module-Based Hydrologic Analysis System for Agricultural Watersheds Including Reservoirs and Irrigation Districts

Abstract. The objective of this study is to develop a module-based hydrologic analysis system for agricultural watersheds, MASA that is capable of analyzing hydrologic components for the upstream and downstream of agricultural reservoirs, and calibrating hydrologic models automatically based on multi-objective optimization. MASA was developed based on Simulink, and can be used for hydrologic analyses of upstream and downstream watersheds, by dividing an agricultural watershed into upstream and downstream with respect to the reservoir. MASA consists of four lumped hydrologic modules, analysis modules for irrigation districts and reservoir water balance, and a multi-objective optimization module, which are operated in conjunction with one another. By applying MASA to the Idong Reservoir watershed, it was found that a long-term data of upstream inflow can be produced from limited measurements. Furthermore, it was found from the simulation of downstream streamflow that the hydrological components of the upstream and downstream of the reservoir are well simulated through a complex interaction. It is expected that the results of this study will contribute to the decision-making process for efficient water management in agricultural watersheds through a complex hydrologic analysis that accounts for the interaction between upstream and downstream of reservoirs.