Every year, debris flows cause huge damage in mountainous areas. Due
to population pressure in hazardous zones, the socio-economic impact
is much higher than in the past. Therefore, the development of indicative
susceptibility hazard maps is of primary importance, particularly
in developing countries. However, the complexity of the phenomenon
and the variability of local controlling factors limit the use of
processbased models for a first assessment. A debris flow model has
been developed for regional susceptibility assessments using digital
elevation model (DEM) with a GIS-based approach.. The automatic identification
of source areas and the estimation of debris flow spreading, based
on GIS tools, provide a substantial basis for a preliminary susceptibility
assessment at a regional scale. One of the main advantages of this
model is its workability. In fact, everything is open to the user,
from the data choice to the selection of the algorithms and their
parameters. The Flow-R model was tested in three different contexts:
two in Switzerland and one in Pakistan, for indicative susceptibility
hazard mapping. It was shown that the quality of the DEM is the most
important parameter to obtain reliable results for propagation, but
also to identify the potential debris flows sources.