The protective role of forests is crucial, especially in the face of unavoidable climate change, which increases the risk of torrential processes in the alpine environment. To analyse the effects of large forest disturbances on runoff and torrential processes, we chose the Dovski potok on the southern slope of the Karawanken Mountains, where forests have been severely damaged in the last decade. Using the Kresnik method and the hydrological model ZEMOKOST, five scenarios for the state of the forests were determined and different scenarios of precipitation events were evaluated. According to the Kresnik equation, the 100-year discharge of the Dovski potok is Q100 = 5.8 m³/s, whereas in 1961 it was calculated as Q100 = 6.0 m³/s. The ZEMOKOST model provided different results for the different scenarios. In 2015, before the disturbances, the Q100 = 3.6 m³/s and occurred 45 minutes after the onset of the rainfall. In 2019, after the storms, Q100 increased to 4.9 m³/s and occurred 39 minutes after the onset of rainfall. Analysis of the hydraulic conductivity of the existing dams has shown that it is no longer sufficient to cope with the increase in runoff. In addition, on-site investigations have shown that the erosion debris deposits in the area harbour the risk of debris flows and mudslides that could endanger the village of Dovje.
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