The strength of a population resides in the resilience of its individuals and is closely related
to the stability of its habitat. Stream macro‐invertebrates are sensitive to environmental
changes concerning habitat stability; thus, they require shelter to prevent drift during severe
floods. We propose a novel approach to estimate the impact of flash floods upon the
substrate, by introducing a variable named 'flash‐flood potential'(FFP), which accounts for
the site slope and the average slope of the upstream catchment. We investigate the impact …