Flash floods are very important natural phenomenon today, which is devoted considerable attention in the general public, the media, the public administration system in the professional community The main characteristic of flash floods from the perspective of crisis management is the short time between the cause (torrential precipitation) and the result (flooding of the territory and the emergence of major damages or even loss of life). Right the shortness of time implies that to save lives it is necessary to obtain a warning of impending danger in the shortest possible time after the cause. To do this, a new methodology that enables to identify streams, which may be the subject of intense water runoff and thus manifestations of flash floods was created (Rapant, et al., 2015).