AbstractThresholds for particle entrainment and natural disturbance frequency vary across hydrogeomorphic settings, but urbanization increases the rate and extent of channel erosion and sediment transport in alluvial channels. The urban disturbance regime is a change in the frequency, magnitude, and duration of hydrologically induced disturbance on the stream channel and ecosystem that can lead to geomorphic and ecological degradation. To preserve stream stability and ecological function, stormwater management systems should be optimized to maintain the natural disturbance regime of streambed material within the context of societal and environmental goals. Our proposed framework, based on data from 195 sites across 2 continents, shows that the tools of river mechanics can be used to develop relatively simple, regionally appropriate, streambed-specific guidance for stormwater designers, so that engineers can calibrate stormwater facilities that address the urban stream disturbance regime. In the absence of...