Natural Hazards

Natural hazards include all processes and impact of nature which can be damaging to human beings and material assets.

Natural hazards, due to their causes, are divided into three different groups:

	Hydrological / meteorological hazards Flood: flooding, river bank erosion, debris flow activity Storm: thunderstorm, hail, winter storm, tropical storm Avalanches: snow and ice avalanche Cold wave Drought, heat waves, forest fires

	Geological hazards Mass movements: landslide, rock fall, rock avalanche, slope-type debris flow Earthquake Volcanism Tsunami

Biological hazards Pest infestation

What natural hazards occur in Switzerland?

Switzerland is frequently affected by floods, storms, landslides and avalanches. Less frequent are droughts and heat or cold waves. Strong earthquakes are very rare, but they can occur, as history proved.

Legal regulations provide for the protection of man, environment and valuable material assets from the effects of natural disasters. In Switzerland, they nowadays try to challenge these effects with an integrated risk management approach. According to existing protection deficiencies the necessary measures are defined based upon a thorough risk analysis (hazards and vulnerability assessments) and a risk evaluation. Those measures are then being weighed up due to a cost-benefit analysis and in view of the different interests and the appropriateness.

Natural disasters - even of catastrophic extent - have always occurred in Switzerland. However, as housing schemes became denser and material assets bigger and more valuable, the scale of damage has considerably increased over the past decades.