The U.S. Geological Survey and the HydroGeophysics Group, Aarhus University, describe the benefits of using floaTEM in rivers. USGS has been utilizing the floaTEM in several places, such as the Tallahatchie River, Eel River, Delaware River, and Rainbow Reservoir. Data were collected to achieve high-resolution information about subsurface geologic structures that can be used to delineate fresh-water/saline water contacts, delineate aquifer materials for water-resource investigations, and inform hydrogeologic models.