The aim of this study is to evaluate the flow capacity of twenty selected profiles of torrent Gidra in the village of Píla (Malé Karpaty) compared to N-year flows. Gidra caused significant damage in the village during the destructive flash flood on the 7th of June, 2011. In the area of the watershed has fallen within 3 hours up to 120 milimeters of rainfall (annual rainfall is 600 milimiters), this extreme rainfall caused the flood. We have calculated N-year flows in 20 selected profiles of the torrent directly in the village municipality as their overflow poses greatest danger to life and property. In this work we continue to deal with the problems of flash floods in small watersheds, flash flood protection, prevention and the causes of these floods. We propose several flood control and precautionary measures for the studied watershed. Furthermore, we propose specific solutions to increase the flow capacity of profiles endangering the village. The thesis introduces the concept of a flash-flood detection system and the extreme rainfall detector.