This dataset comprises four tables containing channel survey cross section data, field observations including channel width and bank material, measured surface water velocity, and alluvial grain size data collected along the North Fork Fortymile River near a man-made meander cutoff called The Kink. The data release also contains eight field photos used to obtain grain size distribution; four photos annotated with measured grains linked to the grain size data table by the fields "meas" and "img."