Extent, perception and mitigation of damage due to high groundwater levels in the city of Dresden, Germany

Abstract

Abstract. Flood risk analysis and management plans mostly neglect groundwater flooding, i.e. high groundwater levels. However, rising groundwater may cause considerable damage to buildings and infrastructure. To improve the knowledge about groundwater flooding and support risk management, a survey was undertaken in the city of Dresden (Saxony, Germany), resulting in 605 completed interviews with private households endangered by high groundwater levels. The reported relatively low flood impact and damage of groundwater floods in comparison with mixed floods was reflected by its scarce perception: Hardly anybody thinks about the risk of groundwater flooding. The interviewees thought that public authorities and not themselves, should be mainly responsible for preparedness and emergency response. Up to now, people do not include groundwater risk in their decision processes on self protection. The implementation of precautionary measures does not differ between households with groundwater or with mixed flood experience. However, less households undertake emergency measures when expecting a groundwater flood only. The state of preparedness should be further improved via an intensified risk communication about groundwater flooding by the authorities. Conditions to reach the endangered population are good, since 70% of the interviewed people are willing to inform themselves about groundwater floods. Recommendations for an improved risk communication are given.

The determinants of private flood mitigation measures in Germany — Evidence from a nationwide survey

“…For flood-prone areas in Germany, it seems that insured households take more private flood mitigation measures than non-insured, not less (Thieken et al 2006). Turning to the effect of expected government relief, some authors indeed report negative correlations with private mitigation (Botzen et al 2009;Grothmann and Reusswig 2006;Kreibich et al 2009). However, the charity hazard is not always clearly visible in the data and some estimations fail to discover significant relationships (Bichard and Kazmierczak 2012;Grothmann 2005 for the Rhein area; Koerth et al 2013).…”

“…Their approaches allow for a very detailed analysis of the impact of flood experiences and effectiveness of mitigation measures, but general conclusions concerning the dissemination and determinants of private flood mitigation in the studied countries are rarely possible. Existing empirical, survey-based studies include many analyses from the Netherlands van den Bergh 2009, 2013;Kievik and Gutteling 2011;Terpstra and Lindell 2012;Zaalberg et al 2009) and Germany (Bubeck et al 2013;Grothmann and Reusswig 2006;Grothmann 2005;Koerth et al 2013;Kreibich et al 2005Kreibich et al , 2009Thieken et al 2007). More literature is available on private flood mitigation e.g.…”

Damage estimation of subterranean building constructions due to groundwater inundation – the GIS-based model approach GRUWAD

“…The city is situated in the Elbe River valley and was strongly affected by the flood of the river and its tributaries in 2002. The city had a total inundation area by surface water of about 30 km 2 (LH Dresden, 2005), which is 25 % of the settlement area (Kreibich et al, 2009). Together with extreme rainfall, the interaction between the river and the groundwater was the main cause of significant rising groundwater levels.…”

“…The interviews were undertaken in August and September 2007 by the SOKO-Institute, Bielefeld, Germany and first referred to in Kreibich et al (2009). In total 605 persons of private households in the affected area were interviewed.…”

“…The challenges to understand and to describe groundwater inundation or groundwater flooding processes as well as their consequences are shown in Macdonald et al (2008), Kreibich et al (2009), Cobby et al (2009), and Hughes et al (2011). In addition, Kreibich and Thieken (2008) explain relevant fundamentals for damage assessment of groundwater inundation and the requirement of new specific loss models.…”