Regional Mountain Conference

In the European Alps, debris flows represent one of the most severe natural hazards. Causing major damage and fatalities, they remain a persistent threat to Alpine communities. Minimising the risks associated with debris flows is therefore still of great importance today.

The way in which debris flow processes are explained and understood, and the strategies used to minimise impacts on lives, infrastructure and agricultural land, have changed throughout human history. The development of debris flow management is strongly influenced by technological achievements (e.g., new transport and construction opportunities), a growing understanding of natural hazard processes, governmental changes, and in the variability in the perception and acceptance of debris flow related risks. The introduction of the first government regulations (Torrent Control Act) and the formation of new authorities responsible for torrent control in the late 19th century were important steps towards improving organisation and coordination in the management of debris flow events. Recent debris flow management strategies typically involve complex combinations of mitigation measures, including planning, monitoring and early warning, in addition to structural protection measures. However, each Alpine country has its own history of developing debris flow mitigation strategies.

Based on a literature review, we identify and analyse key criteria for the development of debris flow management strategies in Alpine countries and summarise the key findings in a timeline. Overall, this study provides a comprehensive overview of the changing and evolving approaches to debris flow management in the European Alps over the last 150 years. These insights can serve as a source of inspiration for possible ways of dealing with natural hazards, while also demonstrating limitations of transferring knowledge between practitioners, government and academia.