Identifying Potential Locations of Hydrologic Monitoring Stations Based on Topographical and Hydrological Information

In-situ hydrometric gauges are considered the most trusted source of information in hydrology. They are crucial for effective planning, designing and management of water-related projects. In this study, we aim to identify important gauge locations of streamflow and sediment in the Ganga River Basin: (1) by identifying critical nodes (CN) which serve as pathways for the transport of water and sediment using the linear integer programming algorithm and (2) by identifying unique gauges among the 207 existing stream gauges based on the streamflow and sediment data using the complex network measure of clustering coefficient. We use 30 years of precipitation and temperature data to generate the streamflow and sediment data at the 207 stream gauge locations using the Soil and Water Assessment Tool (SWAT). Results show that the highest number of CN is found in the eastern zone of the basin, followed by the northern and southern zones. A total of 126 CN, 51 unique streamflow gauges, and 85 unique sediment gauge locations are identified. Combining the critical nodes and unique gauges, we identify 177 and 211 potential streamflow and sediment gauge locations in the basin, respectively. Results suggest the scope for adding streamflow and sediment gauges at the identified 126 CN locations. The study is important for policymakers for collecting and managing hydrological data, flood forecasters, and river management authorities for detecting sources of pollution, wastewater, etc.