Assessment of Water Cycle in Agricultural Watershed Based on Canal Network Modeling

Abstract

Recently, various factors such as climate change, watershed environment change, and, socio-economic change, have been shown to have a major impact on the hydrological water cycle and on available water resources in agricultural watersheds. Therefore, it is necessary to identify the water cycle elements of watersheds accurately and to quantify them objectively. Agricultural watersheds can be divided into the basin, irrigation facilities such as reservoir and pumping stations, irrigation areas, and water cycle elements such as rainfall and evapotranspiration water supply and demand. A systematic management system of agricultural water cycle should be established through element analysis, module development, and modeling techniques for comprehensive interpretation of agricultural watersheds. This study involved the monitoring and modeling of inlet, outlet, and reservoir to analyze and quantify water cycle elements in the Madun reservoir (located in Anseong, Gyeonggi-do) and Heungeop reservoir (located in Wonju, Gangwon-do). The watershed runoff, water supply and drainage of irrigation canal, and return flow were estimated using the Storm Water Management Model (SWMM) based on analysis of canal networks and hydraulic calculations. These results can be utilized to ensure stable supply of agricultural water resources and to inform water management policies.