Channel reprofiling using roughened channels is a commonly employed technique to remove barriers to aquatic organism passage. Roughened channels often are designed to simulate natural stream beds under self-formed conditions. These structures often use a mix of large boulders that project into the flow field to create complex flow conditions. Complexities in the flow field are intended to provide a range of conditions that facilitate volitional aquatic organism passage through the structure. We measured water depths and velocities on several roughened channels and identified and characterized complex flow conditions within these channels. We obtained bed and bank morphologic data using a robotic total station and point velocities and velocity profiles using a Sontek Flowtracker with a 3‐d probe. These flow conditions were reviewed and evaluated using empirical data from published research and compared with hydraulic models commonly used in the United States to design roughened channels for fish passage projects. Results summarize uncertainties in data collection and evaluation of fish passage projects and limits in the application of 1- and 2-dimensional models for project design. Our efforts are intended to foster discussions on monitoring of roughened channels.