SCS-CN-based approach for estimating collectable rainwater in waterrshed-scale

Research on collectable rainwater is of vital significance for the utilization of rainfall resources and construction of relevant projects. By taking the watershed in Men Tougou district as the research object, this study adopted Remote Sensing and Geographic Information System techniques to extract and analyze the spatial and attribute data of underlying surface. Based on the above data and rainfall of different hydrological years, SCS-CN model was used to compute the runoff coefficient, and GIS was utilized as a tool to analyze spatial distribution. The collectable rainwater resource of the Watershed under 3 kinds of hydro logical frequency years were then calculated with normal year (p=50%) 1.2×107 m3, wet year (p=25%) 2.2×107 m3and dry year (p=75%) 0.8×107 m3. This study provides scientific references for watershed comprehensive management and design of rainwater accumulation and utilization project.