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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 from natural events.


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. As the population continues to grow, more and more buildings are located in at-risk areas.

As such, we look into 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 effective spatial planning, reliable forecasting or technical protective measures. We lay the scientific foundations for risk analysis and for evaluating whether protective measures and warning systems are effective and economical.

As well as scientific and engineering research, this requires economic and social analysis given that major events present 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. In some cases, we also initiate them for experimental purposes (avalanche test site [Link to VdlS]).

Thanks to this measurement data, we now understand better than ever how these natural hazards arise, and are able to simulate the processes within them in increasingly precise computational models. This is useful for developing protective measures and hazard maps.

Contending with climate change

When glaciers melt and permafrost thaws as a result of climate change, this threatens to set in motion enormous quantities of soil, rock and scree – a significant danger to lower lying settlements and transportation infrastructure. This is why we are focusing on mass movements in alpine regions that are triggered by climate change as part of the strategic research initiative "Climate Change Impacts on Alpine Mass Movements", which is set to run from 2017 to 2020.

Forewarned and informed                                                                               

When it comes to warning and prevention systems, we play an important role nationally and occupy a leading position internationally: in winter, the avalanche warning service at the WSL Institute for Snow and Avalanche Research SLF publishes the well-known avalanche bulletin 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 and findings available to the public on internet platforms so that crisis managers can access the information quickly in an emergency.



Forest fires

We examine factors that increase the risk of forest fires and develop tools for predicting them.

Weather and Climate Extremes and Drought

We study weather and climate extremes in Switzerland, for example droughts. This is how we create the basis for dealing with them.

Debris flows and bedload

Mountain torrents on steep terrain can sweep away destructive loads of rock. We investigate these processes to improve protection measures.

High water levels and flooding

Flooding causes a huge amount of damage in Switzerland. We have been laying the foundations for flood forecasting and warnings for over 100 years.

Rockfalls and landslides

We research rockfalls, rock slope failures, hillslope debris flows and landslides to give people and infrastructure in valleys better protection.

Dealing with natural hazards

Responding to and managing natural hazards has a long tradition in Switzerland. Through research and services, we help to reduce the risks posed by...



Am 11. Januar 2016 staute ein Felssturz in Wolhusen LU die Kleine Emme und führte zu Überschwemmungsschäden im Industriequartier der angrenzenden Gemeinde Werthenstein (Foto: ZSO EMME).

Severe weather events in Switzerland gave rise to property damage of about CHF 100 million in 2016. This was revealed by the annual analysis of the...

A synopsis of long-term change in the forests of the Alps shows that rising timber stock in mountain forests has increased the incidence of natural...

Mit einem Kurzvideo über Steinschlagversuche haben Forschende der WSL den SNF-Wettbewerb für wissenschaftliche Bilder in der Kategorie Video-Loops...

Seit 2015 befällt ein asiatisches Bakterium Rosskastanien in der Schweiz und verursacht einen schwarzbraunen, blutähnlichen Ausfluss am Stamm....




Results of a research project aimed at developing a dimensioning concept for flexible debris flow protection systems. The concept involves specially focused research combining laboratory tests, fully instrumented field installations and the corresponding numerical simulations.