The Kalamazoo River Area of Concern (AOC) has multiple dam removals in various stages of completion. Following dam removal, river restoration activities will occur in impacted reaches. Hydrogeomorphic data from relatively undisturbed and hydraulically stable river reaches are commonly used to inform the design parameters of river restoration projects. Reference reaches should have similar prevailing boundary conditions as target restoration reaches, including water and sediment regime, valley and channel slope, valley confinement, bank heights, and riparian vegetation. This dataset characterizes the geomorphology of one reference reach, an approximately 500m reach upstream of Plainwell, MI. The reach has a drainage area of 3166 square kilometers. It is located in the middle of a zone of relatively consistent valley slope of 0.056%, and had a channel slope of 0.035% measured from the water surface profile during this study. The reach has tree lined banks about 0.5 meters (m) high, with abundant large wood along channel margins, and a riffle-pool structure in which gravel riffles common. Bankfull width in the reach varies from 50m to 85m, and valley width varies from 150m to 300m. The reach is predominantly laterally unconfined, but abuts the valley margin at the lower end of the reach. Bathymetric and topographic data were collected in October, 2021 and combined with aerial lidar data collected in 2015 to develop a digital elevation model (DEM) covering the bed, banks, and floodplain. The DEM was used to create 30 cross-sections spanning the river channel and 5 cross-sections spanning the entire valley bottom. Bankfull hydraulic geometry attributes, complexity metrics, and floodplain inundation metrics across a range of flow stages were calculated for each cross section. The DEM was also used to map hydrogeomorphic units in the channel and floodplain using the geomorphon and geomorphic unit tool (GUT) approaches. Large woody debris in the channel was mapped from vegetation returns in the terrestrial lidar data. Additionally, substrate size data were collected in the reference reach in August, 2022. These geomorphic data are delivered in a variety of file formats, organized in a nested structure. Details on the overall structure and organization of the files in the data release are contained in a README file. Additional details on methods and uses of the datasets are contained within the metadata files associated with each particular dataset.