The research has been conducted in the area of the settlement Belca in Gorenjska region. The field work included the monitoring (RGB images) of rockfall site using unmanned aerial vehicle. In the Pix4D Mapper, a cloud of points and a true orthophoto (TOF) were generated and in the ArcMAP software a digital elevation model (DEM) was created. On the basis of the RGB, TOF and DEM recordings, the potential amount of rocky material which can still detach was estimated (118,000 m3) at the rockfall site. According to the results of the r.avaflow model, 116,000 m3 of rocky material can be deposited in the Belca torrent. This amount was later used as an input data for the debris flow modeling (r.avaflow). In total, 10 debris flow scenarios were tested (depending on the volume of debris in the debris flow and the amount of triggered material). The results have shown us that there is still a possibility of further detaching of rocky material and that there is a possibility of a debris flow event that could endanger the Belca settlement.