A web-based tool for watershed delineation considering lakes and reservoirs

Lakes have significant impacts on watershed hydrology. However, until now, no web-based tool has been available for watershed delineation considering lakes. In this study, we developed a tool to address this, enabling non-exports to delineate watersheds. First, a conceptual data model was proposed to represent related spatial units and their flow relationships, including rivers, lakes, river sub-basins, lake hillslopes, and flow paths. Subsequently, a web-based tool was designed and implemented, which enables users to select an area of interest and obtain watershed delineation results without the need for software installation or data preparation. This tool also supports for the customization of data and parameters. Two case studies, conducted at the Fushi Reservoir and Mahu Lake, demonstrated the system's usability. To our knowledge, this study presents the first web-based tool for watershed delineation that considers lakes, and it has great potential for applications in watershed modeling and management. •This is the first web-based tool for watershed delineation considering lakes.•River sub-basins, lake hillslopes, and flow paths are delineated simultaneously.•Topological connections among units are established.•The tool makes watershed delineation accessible for non-expert users.