A geo-hydro-mechanical approach to landslide hazard assessment and mitigation: a successful application in southern Italy

Landslides are recognized as part of the geological hazards. They represent a variety of slope failure processes, which could be predisposed by hydrological, hydrogeological and mechanical slope features, or triggered by climatic events, along with earthquakes, wildfires, snowmelt and anthropogenic activities. Landslide hazard is a function of landslide susceptibility (spatial propensity to landsliding) and time-based probability of occurrence of the landslide process. The present paper intends to contribute to the dissemination of quantitative hazard assessment methods at the small scale using a deterministic approach, and to show that this effort may be beneficial to improve disaster risk reduction policies in landslide prone areas. To this aim, a methodology for the quantitative assessment and mitigation of landslide hazard at small scale is presented in the paper. The proposed methodology, known as Multiscalar Method for Landslide Mitigation (MMLM), could be applied everywhere in the world, being based on objective geo-hydro-mechanical diagnoses of the landslide processes. The paper also describes the application of the MMLM in the Daunia region of Southern Italy. Within the Priority Action 1 of the Sendai Framework (understanding disaster risk), the MMLM starts from the understanding of the landslide mechanisms and of the relating hazard to derive a diagnosis based on a deterministic approach. Accordingly, the MMLM is capable to address the selection of the most appropriate landslide mitigation measures, using either structural, or non-structural interventions, and to enhance the resilience of the assets and environments within which landslides take place