These data are high-resolution bathymetry (river bottom elevation) in XYZ format, generated from the February 14, 2017, topographic and hydrographic survey of the Des Plaines River in an area centered approximately 0.3 miles downstream of Brandon Road Lock and Dam at Joliet, Illinois. Hydrographic data were collected using a multibeam echo-sounder (MBES) with integrated inertial navigation solution (INS) mounted on a marine survey vessel. Data were collected as the vessel traversed the river along survey lines distributed throughout the area. Data collection software integrated and stored the depth data from the multibeam sonar and the horizontal and vertical position and attitude data of the vessel from the INS in real time. Data processing required computer software to extract bathymetry data from the raw data files and to summarize and map the information.