TY - JOUR
T1 - Damage assessment in Braunsbach 2016
T2 - Data collection and analysis for an improved understanding of damaging processes during flash floods
AU - Laudan, Jonas
AU - Rözer, Viktor
AU - Sieg, Tobias
AU - Vogel, Kristin
AU - Thieken, Annegret H.
N1 - Funding Information:
Acknowledgements. The presented work was developed within the framework of the Research Training Group “Natural Hazards and Risks in a Changing World” (NatRiskChange) funded by the Deutsche Forschungsgemeinschaft (DFG; GRK 2043/1). We further appreciate the help of Benjamin Winter, working at the alpS GmbH in Innsbruck, Austria, as well as giving thanks to Melanie Eckle, Benjamin Herfort, Carolin Klonner and Chiao-Ling Kuo from the University of Heidelberg for supporting the damage assessment in Braunsbach and providing additional mobile tablets for the data acquisition. Special thanks to the contribution of Viktor Rözer, who was partly funded by the German Ministry of Education and Research (BMBF, 03G0846B) via the project “EVUS – Real-Time Prediction of Pluvial Floods and Induced Water Contamination in Urban Areas”.
Publisher Copyright:
© Author(s) 2017.
PY - 2017/12/6
Y1 - 2017/12/6
N2 - Flash floods are caused by intense rainfall events and represent an insufficiently understood phenomenon in Germany. As a result of higher precipitation intensities, flash floods might occur more frequently in future. In combination with changing land use patterns and urbanisation, damage mitigation, insurance and risk management in flash-flood-prone regions are becoming increasingly important. However, a better understanding of damage caused by flash floods requires ex post collection of relevant but yet sparsely available information for research. At the end of May 2016, very high and concentrated rainfall intensities led to severe flash floods in several southern German municipalities. The small town of Braunsbach stood as a prime example of the devastating potential of such events. Eight to ten days after the flash flood event, damage assessment and data collection were conducted in Braunsbach by investigating all affected buildings and their surroundings. To record and store the data on site, the open-source software bundle KoBoCollect was used as an efficient and easy way to gather information. Since the damage driving factors of flash floods are expected to differ from those of riverine flooding, a post-hoc data analysis was performed, aiming to identify the influence of flood processes and building attributes on damage grades, which reflect the extent of structural damage. Data analyses include the application of random forest, a random general linear model and multinomial logistic regression as well as the construction of a local impact map to reveal influences on the damage grades. Further, a Spearman's Rho correlation matrix was calculated. The results reveal that the damage driving factors of flash floods differ from those of riverine floods to a certain extent. The exposition of a building in flow direction shows an especially strong correlation with the damage grade and has a high predictive power within the constructed damage models. Additionally, the results suggest that building materials as well as various building aspects, such as the existence of a shop window and the surroundings, might have an effect on the resulting damage. To verify and confirm the outcomes as well as to support future mitigation strategies, risk management and planning, more comprehensive and systematic data collection is necessary.
AB - Flash floods are caused by intense rainfall events and represent an insufficiently understood phenomenon in Germany. As a result of higher precipitation intensities, flash floods might occur more frequently in future. In combination with changing land use patterns and urbanisation, damage mitigation, insurance and risk management in flash-flood-prone regions are becoming increasingly important. However, a better understanding of damage caused by flash floods requires ex post collection of relevant but yet sparsely available information for research. At the end of May 2016, very high and concentrated rainfall intensities led to severe flash floods in several southern German municipalities. The small town of Braunsbach stood as a prime example of the devastating potential of such events. Eight to ten days after the flash flood event, damage assessment and data collection were conducted in Braunsbach by investigating all affected buildings and their surroundings. To record and store the data on site, the open-source software bundle KoBoCollect was used as an efficient and easy way to gather information. Since the damage driving factors of flash floods are expected to differ from those of riverine flooding, a post-hoc data analysis was performed, aiming to identify the influence of flood processes and building attributes on damage grades, which reflect the extent of structural damage. Data analyses include the application of random forest, a random general linear model and multinomial logistic regression as well as the construction of a local impact map to reveal influences on the damage grades. Further, a Spearman's Rho correlation matrix was calculated. The results reveal that the damage driving factors of flash floods differ from those of riverine floods to a certain extent. The exposition of a building in flow direction shows an especially strong correlation with the damage grade and has a high predictive power within the constructed damage models. Additionally, the results suggest that building materials as well as various building aspects, such as the existence of a shop window and the surroundings, might have an effect on the resulting damage. To verify and confirm the outcomes as well as to support future mitigation strategies, risk management and planning, more comprehensive and systematic data collection is necessary.
UR - http://www.scopus.com/inward/record.url?scp=85037721952&partnerID=8YFLogxK
U2 - 10.5194/nhess-17-2163-2017
DO - 10.5194/nhess-17-2163-2017
M3 - Article
AN - SCOPUS:85037721952
SN - 1561-8633
VL - 17
SP - 2163
EP - 2179
JO - Natural Hazards And Earth System Sciences
JF - Natural Hazards And Earth System Sciences
IS - 12
ER -