The aim of the investigation was to estimate factors responsible for sustaining riverine communities in stream sections with various bank regulation systems. The research were conducted on Porebianka stream in the Polish Western Carpathians, where 10 different types of river regulations were chosen for the analysis (strong incision without alluvial deposits, redeposition with sand and gravel banks, concrete revetment walls along the banks, channel with banks lined with rip-rap and reference unmanaged cross- section). We conclude that the carabid beetles assemblages of the studied river sections respond mainly to hydraulic parameters of the stream. Elimination of frequent natural bank inundation (due to the regulations of the banks) is the main factor responsible for the impoverishment and extinction of riverine communities.