Indicator natural hazards

Damage caused by floods, landslides, debris flows and fall processes

Floods, debris flows, landslides and fall processes can cause significant damage. The extent of the damage is influenced by the use of built-up area and the intensity and spatial extent of the natural hazard events. Hence it also depends on the measures taken to protect human life, the environment and material assets. The amount of losses associated with such events is an indicator of, first, the success of the preventive measures implemented to protect against natural hazards and, second, the vulnerability of buildings and infrastructure.

Assessment of the state
poor poor
Assessment of the trend
impossible to evaluate impossible to evaluate
Damage caused by floods, debris flows, landslides and fall processes 2018: 199.96 Damage caused by floods, debris flows, landslides and fall processes 2017: 175.24 Damage caused by floods, debris flows, landslides and fall processes 2016: 98.1 Damage caused by floods, debris flows, landslides and fall processes 2015: 147.98 Damage caused by floods, debris flows, landslides and fall processes 2014: 100.67 Damage caused by floods, debris flows, landslides and fall processes 2013: 125 Damage caused by floods, debris flows, landslides and fall processes 2012: 38.89 Damage caused by floods, debris flows, landslides and fall processes 2011: 118.03 Damage caused by floods, debris flows, landslides and fall processes 2010: 62.03 Damage caused by floods, debris flows, landslides and fall processes 2009: 26.05 Damage caused by floods, debris flows, landslides and fall processes 2008: 22.97 Damage caused by floods, debris flows, landslides and fall processes 2007: 721.31 Damage caused by floods, debris flows, landslides and fall processes 2006: 75.99 Damage caused by floods, debris flows, landslides and fall processes 2005: 3105.63 Damage caused by floods, debris flows, landslides and fall processes 2004: 51.09 Damage caused by floods, debris flows, landslides and fall processes 2003: 77.15 Damage caused by floods, debris flows, landslides and fall processes 2002: 371.89 Damage caused by floods, debris flows, landslides and fall processes 2001: 85.26 Damage caused by floods, debris flows, landslides and fall processes 2000: 776.45 Damage caused by floods, debris flows, landslides and fall processes 1999: 750.18 Damage caused by floods, debris flows, landslides and fall processes 1998: 46.5 Damage caused by floods, debris flows, landslides and fall processes 1997: 217.23 Damage caused by floods, debris flows, landslides and fall processes 1996: 36.88 Damage caused by floods, debris flows, landslides and fall processes 1995: 93.48 Damage caused by floods, debris flows, landslides and fall processes 1994: 240.4 Damage caused by floods, debris flows, landslides and fall processes 1993: 1050.01 Damage caused by floods, debris flows, landslides and fall processes 1992: 72.55 Damage caused by floods, debris flows, landslides and fall processes 1991: 53.3 Damage caused by floods, debris flows, landslides and fall processes 1990: 373.92 Damage caused by floods, debris flows, landslides and fall processes 1989: 17.39 Damage caused by floods, debris flows, landslides and fall processes 1988: 176.62 Damage caused by floods, debris flows, landslides and fall processes 1987: 1770.15 Damage caused by floods, debris flows, landslides and fall processes 1986: 177.49 Damage caused by floods, debris flows, landslides and fall processes 1985: 76.58 Damage caused by floods, debris flows, landslides and fall processes 1984: 159.01 Damage caused by floods, debris flows, landslides and fall processes 1983: 84.22 Damage caused by floods, debris flows, landslides and fall processes 1982: 65.16 Damage caused by floods, debris flows, landslides and fall processes 1981: 90.54 Damage caused by floods, debris flows, landslides and fall processes 1980: 41.94 Damage caused by floods, debris flows, landslides and fall processes 1979: 88.18 Damage caused by floods, debris flows, landslides and fall processes 1978: 1045.29 Damage caused by floods, debris flows, landslides and fall processes 1977: 509.02 Damage caused by floods, debris flows, landslides and fall processes 1976: 35.61 Damage caused by floods, debris flows, landslides and fall processes 1975: 321.83 Damage caused by floods, debris flows, landslides and fall processes 1974: 61.72 Damage caused by floods, debris flows, landslides and fall processes 1973: 219.72 Damage caused by floods, debris flows, landslides and fall processes 1972: 42.72
*adjusted for inflation, based on 2018 prices

Data for the graph: Excel
Source: WSL
Comment

Between 1972 and 2018, floods and debris flows caused damage to the tune of CHF 13 billion. The damage caused by landslides and fall processes totalled at one billion. Hence, the total cost of damage arising from these natural events was CHF 14; this corresponds to an average annual cost of around CHF 305 million.

The amount of losses is primarily dictated by individual hazard events. For example, the floods of August 2005 alone generated damage totalling around CHF 3 billion. Half of the damage is accounted for by the five biggest individual hazard events.

According to nationally available data, approximately 1.8 million people, that is around 20 percent of the Swiss population, live in areas at risk from flooding. Approximately 1.7 million or 30 percent of the country’s jobs are also located in such areas and around 25 percent of material assets (total approximately CHF 840 billion[1]) can be found in potential flood areas. A large proportion of economic value creation also takes place there. The existing protective infrastructure protects these areas against frequent flood events. Without this protective infrastructure, losses would be significantly higher.

Damage can be prevented or limited if the the hazards are known. Therefore the compilation of hazard maps, their continuous updating and their consistent implementation are matters of extreme urgency. Hazard potential can be limited through hazard-appropriate land-use. Buildings and infrastructure must be designed in a way that avoids major damage. Preventive measures (e.g. hazard prevention structures) must be designed in a robust way which ensures that they withstand excess loads and are able to be adapted to new conditions (climate change). The residual risks must be limited through comprehensive emergency planning and optimised warning and alerting systems.

Absolute safety in dealing with natural hazards is impossible to achieve. The analysis of major flood events, in particular the OWARNA project, have shown that consistent implementation of modern flood protection strategies and improved alerting and alarm systems would enable the avoidance of up to 20% of the damage. For this reason the indicator state is evaluated as negative. The development is not evaluated as the strong annual fluctuations and relatively short monitoring period do not allow clear conclusions to be drawn.

 

Method

As mandated by the Federal Office for the Environment, the Swiss Federal Institute of Forest, Snow and Landscape Research WSL has been collecting data systematically on storm damage in Switzerland since 1972. The hazard processes floods, debris flows, landslides and rockfall (since 2002) are surveyed. The surveys are mainly based on reports from approximately 3,000 Swiss newspapers and magazines and – in the case of extensive hazard events – the information provided by the cantons and insurance companies.

[1] According to the study “Die volkswirtschaftliche Bedeutung der Immobilienwirtschaft der Schweiz “ (“The economic significance of the property market in Switzerland”) (Staub P., Rütter H., 2014), the construction value of Switzerland’s buildings is CHF 3,355 billion.

 
Last updated on: 27.03.2019

Further information

Links

inidkatoren_hirun

Indicators

Search and list of all indicators

https://www.bafu.admin.ch/content/bafu/en/home/themen/thema-naturgefahren/naturgefahren--daten--indikatoren-und-karten/naturgefahren--indikatoren/indikator-naturgefahren.pt.html/aHR0cHM6Ly93d3cuaW5kaWthdG9yZW4uYWRtaW4uY2gvUHVibG/ljL0FlbURldGFpbD9pbmQ9R0UwMTcmbG5nPWVuJlN1Ymo9Tg==.html