Natural hazards: In brief

With its many mountains and bodies of water, Switzerland is highly prone to natural hazards. Extensive and growing settlements and infrastructure increase the potential for damage. Climate change will exacerbate the existing risks and create new ones, such as more frequent and intense heavy precipitation and longer periods of drought. Natural hazards will increasingly occur in areas that have not been affected thus far, and at unusual times of the year. This makes a well-informed, forward-looking approach to natural hazards even more important.


1. Climate change, hazard processes and how they are changing (drivers)

Switzerland is regularly affected by floods and debris flows, landslides, fall processes (rockfall and rock avalanches), avalanches and storms. Forest fire, drought, heat waves and cold waves can also occur. Strong earthquakes are rare; however, as history shows, they can occur in Switzerland too and pose a significant risk.

It is to be expected that natural events in Switzerland will become more frequent and more intense with climate change. Events can also occur more frequently in areas that have been spared up to now and at unusual times of the year.


2. Land use and hazard situation (pressures)

To enable an adequate response to natural hazards, the danger they pose must be known. Different types of hazard documentation provide such information. A key example of such documentation, hazard maps indicate the locations in Switzerland where built-up areas and transport routes are threatened by natural hazards, the extent of the associated dangers, and their probability of occurrence.

Natural events only become hazards if people, buildings or infrastructure are affected by them. Due to the intensification of land use and its expansion into potentially endangered areas, the possible damage is constantly increasing. Thus, information about land use is another important basis for integrated risk management for the protection of people and material assets against natural hazards.


3. Risks (state)

Risk is generally understood as the possibility that damage could arise as a result of a particular event. Risks can be identified and assessed and thus act as a yardstick for safety.

The risks resulting from natural hazards have increased in recent decades. The main reason for this is the greater potential for damage resulting from the growth of the population, the expansion of settlement areas into threatened regions and the increase in value of public infrastructures and private material assets.

Around one fifth of the Swiss population is currently exposed to the risk of flooding, and around 7% of people live in areas that might be affected by avalanches, landslides, rockslides or rockfalls. Just under two million jobs, or one third of the national total, are also located in these areas.


4. Damage and lessons to be learnt (impact)

Switzerland has been the scene of natural disasters since time immemorial. Nine out of ten Swiss communes have already been affected by natural hazards.

Even nowadays, natural events can still claim lives and cause extensive damage to the environment and material assets. Despite the considerable improvement in the protection provided against natural hazards, the risk of natural hazards is constantly increasing due to the intensification of land use and the growing frequency of extreme events and will continue to increase unless the trend is monitored, evaluated and controlled in an aware and forward-thinking manner.

Between 1972 and 2023, the cost of the average damage caused by floods, debris flows and fall processes in Switzerland was around CHF 306 million per year.   Over 90% of the damage resulted from flooding and debris flows. Avalanches, rockslides and rockfalls, on the other hand, more often give rise to above-average fatalities and injuries. Major property damage is also caused by winter storms and summer hail storms. Drought damages agricultural crops, moisture-dependent ecosystems and forests, and leads to the risk of forest fires. Earthquakes are the natural hazard with the greatest potential for damage in Switzerland. Powerful earthquakes are rare, but can occur at any time and in any part of the country – even outside the known earthquake areas.

Extraordinary events provide an opportunity for analysing their causes and impact and to learn from them. Thus it is possible to identify gaps in the hazard documentation and test the effectiveness of existing protective measures. 


5. Dealing with natural hazards (responses)

Avoiding endangered areas by means of spatial planning measures or risk-based spatial planning is the most effective contribution to eliminating risks. 

In cases where this is not possible, technical, biological or organisational measures are implemented to avert the danger or reduce the damage. An existing protective effect is ensured in the long term by proper maintenance of water bodies, protective forests and protective structures.

The permanent monitoring of hazard processes ensures that both imminent dangers and general changes in the hazard situation can be identified at n early stage. Damage can be reduced through timely warning, alerting and information in the case of a hazard event.

The protective measures implemented in recent years have proved effective in many locations. Projects for eliminating known priority protection deficits are co-financed by the federal authorities in the context of the programme agreements or through single projects. In 2016, the Federal Council adopted 67 measures to improve safety against natural hazards. Currently, 50% of these measures have been implemented. Natural hazard protection is based on the 'Management of risks from natural hazards' strategy as a joint task in which all stakeholders have a contribution to make.

  • In Switzerland, the communes and cantons are primarily responsible for protection against natural hazards.
  • The federal authorities adopt a strategic leadership role and provide financial and expert support to the cantons.
  • All persons potentially affected by natural hazards, such as homeowners or infrastructure operators, assume their own responsibility by constructing their building property in accordance with natural hazards and increasing protection with the help of property protection measures. Personal and operational precautions, as well as correct behaviour in the event of an incident, also reduce the damage.
  • The insurance companies provide insurance against potential damage by natural forces.

Since 2001, the federal government has coordinated its activities in the area of earthquake preparedness as part of a programme of measures. The only way to reduce damage during earthquakes is to build earthquake-resistant new buildings and to implement measures aimed specifically at improving the earthquake safety of existing buildings by ensuring consistent application of the relevant standards. Insurance against earthquake damage exists only on a voluntary basis.

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Last modification 19.04.2024

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