This dataset contains topographic cross sections spanning the river channel for an approximately 500 meter (m) reach of the Kalamazoo River upstream of Plainwell, Michigan (MI). The 30 cross sections are oriented perpendicular to the channel and spaced evenly along the 500m reach to represent variability in channel geometry. Bankfull hydraulic geometry attributes and complexity metrics were calculated for each cross section. The cross section data were extracted from a digital elevation model (DEM) comprising topographic and bathymetric data collected by several different methods. Bathymetric data in the river channel were collected in October, 2021 with a single beam sonar and Acoustic Current Doppler Profiler operated along two longitudinal transects and 48 cross-sectional transects, respectively. River bank topographic data were collected with a backpack-mounted terrestrial lidar unit concurrently with the bathymetric data. Floodplain elevations were obtained from aerial lidar data collected in 2015. All ground points from the respective datasets were projected to the same coordinate system and used to generate a DEM with 1m resolution covering the channel bed, banks, and floodplain, and valley walls through the reference reach. Cross-section data are provided in tabular and graphical form in an Excel spreadsheet. The data are also provided as individual CSV files for each cross-section (in a zipped archive), which contain X and Y coordinates in addition to elevations and cross-sectional distance values. Cross-sections are named by their distance, in meters, downstream from the start of the reference reach. The spatial location of the cross-sections is provided by an associated polyline shapefile included in this data release.