Application of ArcHydro Tool, Geospatial Technologies and Digital Elevation Model for Watershed Modeling: A Case of Nepal Himalaya
Watershed modeling plays a crucial role in hydrological analysis, primarily involving the essential task of delineating the catchment area into watershed and sub-watershed components for convenient characterization. This study specifically focuses on the delineation of watersheds using ArcHydro tool in conjunction with geospatial technologies. Arc-Hydro, developed as an extension to the ArcGIS software, functions as a model specially designed for constructing hydrologic information systems. It integrates geospatial and temporal water resources data to support hydrologic modeling and analysis. ArcHydro offers manual extraction options, enhancing efficiency in extensive watershed studies and facilitating dataset management in modeling efforts. However, it is imperative to adhere to the correct sequence, as errors in using any tool within the sequence can impede the successful execution of the entire ArcHydro model, thereby hindering the intended delineation of watershed and sub-watersheds. This challenge is particularly noteworthy for beginner who may be prone to such mistakes. In this study, a high-resolution 12.5 m Digital Elevation Model (DEM) of the Sudurpashchim province was used to delineate the catchment area and drainage network of the Budhiganga waterbody. The use of this tool ensures that users can achieve the desired results effectively in a single click. This study highlights the effective use of ArcHydro tool with DEM for watershed and sub-watershed delineation. Additionally, the study recommends proper user training to avoid errors and ensure accurate hydrological modeling.