Damage assessment in Braunsbach 2016: data collection and analysis for an improved understanding of damaging processes during flash floods

Abstract. 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.

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Brief communication: On-site data collection of damage caused by flash floods: Experiences from Braunsbach, Germany, in May/June 2016

10.5194/nhess-2016-387 ◽

2016 ◽

Cited By ~ 1

Author(s):

Jonas Laudan ◽

Viktor Rözer ◽

Tobias Sieg ◽

Kristin Vogel ◽

Annegret H. Thieken

Keyword(s):

Data Collection ◽

Open Source Software ◽

Flash Flood ◽

Flash Floods ◽

Efficient Tool ◽

Rainfall Events ◽

Ex Post ◽

Riverine Floods ◽

Available Information ◽

Post Hoc

Abstract. Flash floods are caused by intense rainfall events and represent an insufficiently understood phenomenon in Germany. The understanding of damage caused by flash floods requires ex-post collection of relevant but yet sparsely available information for further research. Thus, on-site data collection was carried out after the flash flood event on 29 May 2016 in Braunsbach, Germany, using open source software as helpful and efficient tool for data acquisition and evaluation. The post-hoc analysis links process intensities to damage and reveals differences in damage driving factors of flash floods compared to riverine floods, indicating that also risk patterns vary among different flood types.

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Ex post damage assessment: an Italian experience

Natural Hazards and Earth System Science ◽

10.5194/nhess-14-901-2014 ◽

2014 ◽

Vol 14 (4) ◽

pp. 901-916 ◽

Cited By ~ 49

Author(s):

D. Molinari ◽

S. Menoni ◽

G. T. Aronica ◽

F. Ballio ◽

N. Berni ◽

...

Keyword(s):

Data Collection ◽

Damage Assessment ◽

Local Level ◽

Data Gathering ◽

Recovery Phase ◽

Flood Damage ◽

Local Authorities ◽

Damage Models ◽

Ex Post ◽

And Storage

Abstract. In recent years, awareness of a need for more effective disaster data collection, storage, and sharing of analyses has developed in many parts of the world. In line with this advance, Italian local authorities have expressed the need for enhanced methods and procedures for post-event damage assessment in order to obtain data that can serve numerous purposes: to create a reliable and consistent database on the basis of which damage models can be defined or validated; and to supply a comprehensive scenario of flooding impacts according to which priorities can be identified during the emergency and recovery phase, and the compensation due to citizens from insurers or local authorities can be established. This paper studies this context, and describes ongoing activities in the Umbria and Sicily regions of Italy intended to identifying new tools and procedures for flood damage data surveys and storage in the aftermath of floods. In the first part of the paper, the current procedures for data gathering in Italy are analysed. The analysis shows that the available knowledge does not enable the definition or validation of damage curves, as information is poor, fragmented, and inconsistent. A new procedure for data collection and storage is therefore proposed. The entire analysis was carried out at a local level for the residential and commercial sectors only. The objective of the next steps for the research in the short term will be (i) to extend the procedure to other types of damage, and (ii) to make the procedure operational with the Italian Civil Protection system. The long-term aim is to develop specific depth–damage curves for Italian contexts.

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Flood Hazard Mapping Using the Flood and Flash-Flood Potential Index in the Buzău River Catchment, Romania

Water ◽

10.3390/w11102116 ◽

2019 ◽

Vol 11 (10) ◽

pp. 2116 ◽

Cited By ~ 1

Author(s):

Mihnea Cristian Popa ◽

Daniel Peptenatu ◽

Cristian Constantin Drăghici ◽

Daniel Constantin Diaconu

Keyword(s):

Risk Management ◽

Flash Flood ◽

Flood Hazard ◽

Flash Floods ◽

Hazard Mapping ◽

Flood Vulnerability ◽

River Catchment ◽

Potential Index ◽

Vulnerability Maps ◽

Two Indices

The importance of identifying the areas vulnerable for both floods and flash-floods is an important component of risk management. The assessment of vulnerable areas is a major challenge in the scientific world. The aim of this study is to provide a methodology-oriented study of how to identify the areas vulnerable to floods and flash-floods in the Buzău river catchment by computing two indices: the Flash-Flood Potential Index (FFPI) for the mountainous and the Sub-Carpathian areas, and the Flood Potential Index (FPI) for the low-altitude areas, using the frequency ratio (FR), a bivariate statistical model, the Multilayer Perceptron Neural Networks (MLP), and the ensemble model MLP–FR. A database containing historical flood locations (168 flood locations) and the areas with torrentiality (172 locations with torrentiality) was created and used to train and test the models. The resulting models were computed using GIS techniques, thus resulting the flood and flash-flood vulnerability maps. The results show that the MLP–FR hybrid model had the most performance. The use of the two indices represents a preliminary step in creating flood vulnerability maps, which could represent an important tool for local authorities and a support for flood risk management policies.

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Flash floods simulation in a small drainage basin using HEC-RAS hydraulic model

Ovidius University Annals of Constanta - Series Civil Engineering ◽

10.1515/ouacsce-2017-0009 ◽

2017 ◽

Vol 19 (1) ◽

pp. 101-118

Author(s):

Constantin Buta ◽

Geanina Mihai ◽

Mădălina Stănescu

Keyword(s):

Risk Management ◽

Flood Risk ◽

Drainage Basin ◽

Flash Flood ◽

Flash Floods ◽

Flood Risk Management ◽

Drainage Basins ◽

Climate Conditions ◽

Hydraulic Models ◽

Gauging Station

Abstract In recent years, climate conditions has caused extreme hydrological phenomena like flash floods that lead to significant material losses and impact on the environment in Dobrogea Region, Romania. In this context the needs for an integrated and sustainable approach to flash flood risk management even in small drainage basins are necessary, in order to reduce the the potential damages of flash floods in the future. In this study the hydraulic models Hec-Ras and HecGeo-Ras were used in order to simulate the behaviour of the environment at the pressure of the flashfloods in a small drainage basin. The results were validated using the measurements undertaken after the flash-flood event recorded in October, 13th, 2015 as well as the data provided by the Corbu gauging station along time.

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Features of Cross-Correlation Analysis in a Data-Driven Approach for Structural Damage Assessment

Sensors ◽

10.3390/s18051571 ◽

2018 ◽

Vol 18 (5) ◽

pp. 1571 ◽

Cited By ~ 4

Author(s):

Jhonatan Camacho Navarro ◽

Magda Ruiz ◽

Rodolfo Villamizar ◽

Luis Mujica ◽

Jabid Quiroga

Keyword(s):

Correlation Analysis ◽

Damage Assessment ◽

Structural Damage ◽

Cross Correlation ◽

Data Driven ◽

Cross Correlation Analysis ◽

Data Driven Approach

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A Survey of Remote Sensing and Geographic Information System Applications for Flash Floods

Remote Sensing ◽

10.3390/rs13091818 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1818

Author(s):

Lisha Ding ◽

Lei Ma ◽

Longguo Li ◽

Chao Liu ◽

Naiwen Li ◽

...

Keyword(s):

Remote Sensing ◽

Information System ◽

Geographic Information System ◽

Flash Flood ◽

Flash Floods ◽

Geographic Information ◽

Flood Disaster ◽

Future Research ◽

Time Zone ◽

Gis Technologies

Flash floods are among the most dangerous natural disasters. As climate change and urbanization advance, an increasing number of people are at risk of flash floods. The application of remote sensing and geographic information system (GIS) technologies in the study of flash floods has increased significantly over the last 20 years. In this paper, more than 200 articles published in the last 20 years are summarized and analyzed. First, a visualization analysis of the literature is performed, including a keyword co-occurrence analysis, time zone chart analysis, keyword burst analysis, and literature co-citation analysis. Then, the application of remote sensing and GIS technologies to flash flood disasters is analyzed in terms of aspects such as flash flood forecasting, flash flood disaster impact assessments, flash flood susceptibility analyses, flash flood risk assessments, and the identification of flash flood disaster risk areas. Finally, the current research status is summarized, and the orientation of future research is also discussed.

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The 2011 Tohoku Tsunami from the Sky: A Review on the Evolution of Artificial Intelligence Methods for Damage Assessment

Geosciences ◽

10.3390/geosciences11030133 ◽

2021 ◽

Vol 11 (3) ◽

pp. 133

Author(s):

Jérémie Sublime

Keyword(s):

Artificial Intelligence ◽

Case Studies ◽

Damage Assessment ◽

Structural Damage ◽

North East ◽

2011 Tohoku Tsunami ◽

Artificial Intelligence Methods ◽

The Future ◽

Tohoku Tsunami

The Tohoku tsunami was a devastating event that struck North-East Japan in 2011 and remained in the memory of people worldwide. The amount of devastation was so great that it took years to achieve a proper assessment of the economical and structural damage, with the consequences still being felt today. However, this tsunami was also one of the first observed from the sky by modern satellites and aircrafts, thus providing a unique opportunity to exploit these data and train artificial intelligence methods that could help to better handle the aftermath of similar disasters in the future. This paper provides a review of how artificial intelligence methods applied to case studies about the Tohoku tsunami have evolved since 2011. We focus on more than 15 studies that are compared and evaluated in terms of the data they require, the methods used, their degree of automation, their metric performances, and their strengths and weaknesses.

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Structural Damage Assessment Using Output-Only Measurement: Localization and Quantification

Volume 2: Mechanics and Behavior of Active Materials; Structural Health Monitoring; Bioinspired Smart Materials and Systems; Energy Harvesting ◽

10.1115/smasis2013-3008 ◽

2013 ◽

Author(s):

Chin-Hsiung Loh ◽

Min-Hsuan Tseng ◽

Shu-Hsien Chao

Keyword(s):

Damage Detection ◽

Damage Assessment ◽

Structural Damage ◽

Damage Identification ◽

Model Updating ◽

Null Space ◽

Singular Spectrum Analysis ◽

Damage Index ◽

Computation Efficiency ◽

Output Only

One of the important issues to conduct the damage detection of a structure using vibration-based damage detection (VBDD) is not only to detect the damage but also to locate and quantify the damage. In this paper a systematic way of damage assessment, including identification of damage location and damage quantification, is proposed by using output-only measurement. Four level of damage identification algorithms are proposed. First, to identify the damage occurrence, null-space and subspace damage index are used. The eigenvalue difference ratio is also discussed for detecting the damage. Second, to locate the damage, the change of mode shape slope ratio and the prediction error from response using singular spectrum analysis are used. Finally, to quantify the damage the RSSI-COV algorithm is used to identify the change of dynamic characteristics together with the model updating technique, the loss of stiffness can be identified. Experimental data collected from the bridge foundation scouring in hydraulic lab was used to demonstrate the applicability of the proposed methods. The computation efficiency of each method is also discussed so as to accommodate the online damage detection.

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