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In Switzerland, natural hazards such as avalanches, landslides, rockfall, debris flows, flooding and forest fires can cause considerable damage. Through our research and services, we help to protect people against such a danger.


In Switzerland, 23 people are killed on average each year by avalanches alone; flooding and mass movements cause damage amounting to an average of CHF 300 million per year.

Avalanches alone kill an average of 23 people in Switzerland every year; flooding and mass movements cause an average of 300 million Swiss francs in damage every year. As the population continues to grow, more and more buildings are located in at-risk areas. Climate change is causing glaciers and permafrost to melt, threatening to set enormous amounts of rock, earth and debris in motion.

We research how different natural hazards arise; how far, how quickly and how vigorously they develop, and how people can protect themselves accordingly. This may be through for example spatial planning, reliable forecasting, technical protective measures or protection forests. We lay the scientific foundations for risk analysis and evaluating whether protective measures and warning systems are effective and economical.

This requires not just scientific and engineering research, but economic and social research, as well as close cooperation between different stakeholders. The question of how to deal with natural hazards presents politics, government and society with the challenge of finding widely accepted and economically viable risk reduction strategies.

Observation and simulation

In order to understand the processes of natural hazards in detail, we run experimental setups which are unique worldwide. As part of field experiments, we observe the dynamics of avalanches, debris flows, rockfall and landslides under realistic conditions.


Thanks to these field experiments, we now understand better than ever how these natural hazards arise and develop, and are able to simulate the processes with increasingly precise computational models. This is useful for optimising protective measures and hazard maps.

Forewarned and informed                                                                               

When it comes to warning and information systems, we play a leading role: in winter, the avalanche warning service at the WSL Institute for Snow and Avalanche Research SLF publishes the avalanche bulletin. for Switzerland twice a day, while our hydrologists are involved in warning the public about instances of flooding and severe drought.

Forest fires present a real threat in the already dry southern alpine valleys. We record and analyse forest fire events, develop methods and concepts to evaluate the risk of forest fire, and determine the consequences for ecosystems such as protection forests.

We make our data, findings and products available to the public and safety authorities on internet platforms, as apps or in leaflets.


Focus Areas


The WSL research program CCAMM researches mass movements and the impact of climate change in mountain areas.



The research centre for climate change, extremes and natural hazards in alpine regions.


This boulder had a diameter of 3.5 m. Image: Werner Gerber


We research rockfalls so that risks can be assessed and damage prevented, and develop instruments for research and practical use.

Image: Lambert Zufferey


The RAMMS software package can be used to calculate natural hazard processes and assess the influence of protective measures.


Avalanche bulletin and snow situation

The SLF provides continuous information on the current avalanche and snow situation during the winter season.

White Risk

White Risk is a web-based, interactive platform that raises awareness of the avalanche danger off secured slopes.




SLF researchers have developed a method for automatically and reliably mapping avalanches in satellite images.

An international team of researchers has now been able to measure and simulate the resonant swaying of the Matterhorn.

Inserting the seven-ton steel structure with pinpoint accuracy into the concrete check dam under the road bridge over the Illgraben.

The WSL has replaced the force plate used to measure debris-flows in the Illgraben gully near Leuk (VS). It delivered its first data on June 10.

Nach heftigen Gewittern am 2. Juli 2018 schwoll die Navisence stark an und beschädigte die Ufer an diversen Stellen in den Gemeinden Anniviers und Chippis VS.

Floods, landslides and debris flows caused some CHF 200 million of damage in Switzerland in 2018.