Significance of "high probability/low damage" versus "low probability/high damage" flood events

The need for an efficient use of limited resources fosters the application of risk-oriented design in flood mitigation. Flood defence measures reduce future damage. Traditionally, this benefit is quantified via the expected annual damage. We analyse the contribution of "high probability/low...

Full description

Bibliographic Details
Main Authors: B. Merz, F. Elmer, A. H. Thieken
Format: Article
Language:English
Published: Copernicus Publications 2009-06-01
Series:Natural Hazards and Earth System Sciences
Online Access:http://www.nat-hazards-earth-syst-sci.net/9/1033/2009/nhess-9-1033-2009.pdf
_version_ 1811319037229006848
author B. Merz
F. Elmer
A. H. Thieken
author_facet B. Merz
F. Elmer
A. H. Thieken
author_sort B. Merz
collection DOAJ
description The need for an efficient use of limited resources fosters the application of risk-oriented design in flood mitigation. Flood defence measures reduce future damage. Traditionally, this benefit is quantified via the expected annual damage. We analyse the contribution of "high probability/low damage" floods versus the contribution of "low probability/high damage" events to the expected annual damage. For three case studies, i.e. actual flood situations in flood-prone communities in Germany, it is shown that the expected annual damage is dominated by "high probability/low damage" events. Extreme events play a minor role, even though they cause high damage. Using typical values for flood frequency behaviour, flood plain morphology, distribution of assets and vulnerability, it is shown that this also holds for the general case of river floods in Germany. This result is compared to the significance of extreme events in the public perception. "Low probability/high damage" events are more important in the societal view than it is expressed by the expected annual damage. We conclude that the expected annual damage should be used with care since it is not in agreement with societal priorities. Further, risk aversion functions that penalise events with disastrous consequences are introduced in the appraisal of risk mitigation options. It is shown that risk aversion may have substantial implications for decision-making. Different flood mitigation decisions are probable, when risk aversion is taken into account.
first_indexed 2024-04-13T12:36:23Z
format Article
id doaj.art-7691ad23fda943e6b6a5199ef74e723a
institution Directory Open Access Journal
issn 1561-8633
1684-9981
language English
last_indexed 2024-04-13T12:36:23Z
publishDate 2009-06-01
publisher Copernicus Publications
record_format Article
series Natural Hazards and Earth System Sciences
spelling doaj.art-7691ad23fda943e6b6a5199ef74e723a2022-12-22T02:46:39ZengCopernicus PublicationsNatural Hazards and Earth System Sciences1561-86331684-99812009-06-019310331046Significance of "high probability/low damage" versus "low probability/high damage" flood eventsB. MerzF. ElmerA. H. ThiekenThe need for an efficient use of limited resources fosters the application of risk-oriented design in flood mitigation. Flood defence measures reduce future damage. Traditionally, this benefit is quantified via the expected annual damage. We analyse the contribution of "high probability/low damage" floods versus the contribution of "low probability/high damage" events to the expected annual damage. For three case studies, i.e. actual flood situations in flood-prone communities in Germany, it is shown that the expected annual damage is dominated by "high probability/low damage" events. Extreme events play a minor role, even though they cause high damage. Using typical values for flood frequency behaviour, flood plain morphology, distribution of assets and vulnerability, it is shown that this also holds for the general case of river floods in Germany. This result is compared to the significance of extreme events in the public perception. "Low probability/high damage" events are more important in the societal view than it is expressed by the expected annual damage. We conclude that the expected annual damage should be used with care since it is not in agreement with societal priorities. Further, risk aversion functions that penalise events with disastrous consequences are introduced in the appraisal of risk mitigation options. It is shown that risk aversion may have substantial implications for decision-making. Different flood mitigation decisions are probable, when risk aversion is taken into account.http://www.nat-hazards-earth-syst-sci.net/9/1033/2009/nhess-9-1033-2009.pdf
spellingShingle B. Merz
F. Elmer
A. H. Thieken
Significance of "high probability/low damage" versus "low probability/high damage" flood events
Natural Hazards and Earth System Sciences
title Significance of "high probability/low damage" versus "low probability/high damage" flood events
title_full Significance of "high probability/low damage" versus "low probability/high damage" flood events
title_fullStr Significance of "high probability/low damage" versus "low probability/high damage" flood events
title_full_unstemmed Significance of "high probability/low damage" versus "low probability/high damage" flood events
title_short Significance of "high probability/low damage" versus "low probability/high damage" flood events
title_sort significance of quot high probability low damage quot versus quot low probability high damage quot flood events
url http://www.nat-hazards-earth-syst-sci.net/9/1033/2009/nhess-9-1033-2009.pdf
work_keys_str_mv AT bmerz significanceofquothighprobabilitylowdamagequotversusquotlowprobabilityhighdamagequotfloodevents
AT felmer significanceofquothighprobabilitylowdamagequotversusquotlowprobabilityhighdamagequotfloodevents
AT ahthieken significanceofquothighprobabilitylowdamagequotversusquotlowprobabilityhighdamagequotfloodevents