Flood Risk Assessment Based on Flood Hazard and Vulnerability Indexes

Abstract Within this paper, a methodology for assessing the flood risk was developed by extracting the essential factors that favor the generation of flood risk. These factors, that had a sufficient number of data for a proper comparative analysis, are: potentially affected population based on population density, total agricultural area, total built-up area and the historical maximum amount of precipitation recorded in 24 hours. The flood risk assessment is presented in the form of indices calculation for all these factors and maps generated which representing the results of the calculation of the above-mentioned factors and the results of the flood risk index calculation. Urban floods have particularities that must be presented in detail to understand the flood phenomenon, which is why this paper takes into consideration these areas. In order to determine the probability of urban floods, all disturbing factors that may affect the urban area must be taken into account. The method presented in this paper can be used in sectoral planning activities and integrated planning studies, and for damage assessment.

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A Case Study of Flood Risk Evaluation Based on Emergy Theory and Cloud Model in Anyang Region, China

Water ◽

10.3390/w13040420 ◽

2021 ◽

Vol 13 (4) ◽

pp. 420

Author(s):

Zening Wu ◽

Yuhai Cui ◽

Yuan Guo

Keyword(s):

Risk Assessment ◽

Flood Risk ◽

Flood Control ◽

Flood Hazard ◽

Cloud Model ◽

Flood Disaster ◽

Assessment System ◽

Assessment Model ◽

Flood Risk Assessment ◽

Emergy Theory

With the progression of climate change, the intensity and frequency of extreme rainfall have increased in many parts of the world, while the continuous acceleration of urbanization has made cities more vulnerable to floods. In order to effectively estimate and assess the risks brought by flood disasters, this paper proposes a regional flood disaster risk assessment model combining emergy theory and the cloud model. The emergy theory can measure many kinds of hazardous factor and convert them into unified solar emergy (sej) for quantification. The cloud model can transform the uncertainty in flood risk assessment into certainty in an appropriate way, making the urban flood risk assessment more accurate and effective. In this study, the flood risk assessment model combines the advantages of the two research methods to establish a natural and social dual flood risk assessment system. Based on this, the risk assessment system of the flood hazard cloud model is established. This model was used in a flood disaster risk assessment, and the risk level was divided into five levels: very low risk, low risk, medium risk, high risk, and very high risk. Flood hazard risk results were obtained by using the entropy weight method and fuzzy transformation method. As an example for the application of this model, this paper focuses on the Anyang region which has a typical continental monsoon climate. The results show that the Anyang region has a serious flood disaster threat. Within this region, Linzhou County and Anyang County have very high levels of risk for flood disaster, while Hua County, Neihuang County, Wenfeng District and Beiguan District have high levels of risk for flood disaster. These areas are the core urban areas and the economic center of local administrative regions, with 70% of the industrial clusters being situated in these regions. Only with the coordinated development of regional flood control planning, economy, and population, and reductions in the uncertainty of existing flood control and drainage facilities can the sustainable, healthy and stable development of the region be maintained.

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Rapid Global Exposure Assessment for Extreme River Flood Risk Under Climate Change

Journal of Disaster Research ◽

10.20965/jdr.2016.p1128 ◽

2016 ◽

Vol 11 (6) ◽

pp. 1128-1136 ◽

Cited By ~ 3

Author(s):

Youngjoo Kwak ◽

◽

Yoichi Iwami ◽

Keyword(s):

Climate Change ◽

Risk Assessment ◽

Flood Risk ◽

Large Scale ◽

Flood Hazard ◽

Data Availability ◽

Flood Risk Assessment ◽

Daily Data ◽

Extreme Flood ◽

River Flood

Globally, large-scale floods are one of the most serious disasters, considering increased frequency and intensity of heavy rainfall. This is not only a domestic problem but also an international water issue related to transboundary rivers in terms of global river flood risk assessment. The purpose of this study is to propose a rapid flood hazard model as a methodological possibility to be used on a global scale, which uses flood inundation depth and works reasonably despite low data availability. The method is designed to effectively simplify complexities involving hydrological and topographical variables in a flood risk-prone area when applied in an integrated global flood risk assessment framework. The model was used to evaluate flood hazard and exposure through pixel-based comparison in the case of extreme flood events caused by an annual maximum daily river discharge of 1/50 probability of occurrence under the condition of climate change between two periods, Present (daily data from 1980 to 2004) and Future (daily data from 2075 to 2099). As preliminary results, the maximum potential extent of inundation area and the maximum number of affected people show an upward trend in Present and Future.

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Flood hazard and flood risk assessment at the local spatial scale: a case study

Geomatics Natural Hazards and Risk ◽

10.1080/19475705.2016.1166874 ◽

2016 ◽

Vol 7 (6) ◽

pp. 1973-1992 ◽

Cited By ~ 28

Author(s):

Matej Vojtek ◽

Jana Vojteková

Keyword(s):

Risk Assessment ◽

Spatial Scale ◽

Flood Risk ◽

Flood Hazard ◽

Flood Risk Assessment

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Index-based flood risk assessment for Metro Manila

Water Science & Technology Water Supply ◽

10.2166/ws.2020.010 ◽

2020 ◽

Vol 20 (3) ◽

pp. 851-859 ◽

Cited By ~ 1

Author(s):

C. J. Rubio ◽

I. S. Yu ◽

H. Y. Kim ◽

S. M. Jeong

Keyword(s):

Risk Assessment ◽

Land Use Planning ◽

Flood Risk ◽

Flood Hazard ◽

The Philippines ◽

Flood Risk Assessment ◽

Disaster Insurance ◽

Metro Manila ◽

Hazard And Risk ◽

Populated Region

Abstract This study focuses on index-based flood risk assessment in Metro Manila, the capital region of the Philippines and most densely populated region in the country. Its objective is to properly address urban characteristics in flood risk assessment by introducing a specific urban-type set of physical, social, economic and ecological indicators. Analytical hierarchy process (AHP) was used to quantify the optimal selection weights for each of the selected 14 indicators. Five levels of flood risk will be presented in spatial maps using geographic information system (GIS) ranging from Very Low Risk to Very High Risk. Results of this study are expected to aid in understanding flood hazard and risk in Metro Manila. Moreover, the resulting flood risk information can be used as a decision tool in policy making, land-use planning, developing guidelines and countermeasures and flood disaster insurance.

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Flood Hazard, Vulnerability and Risk Assessment for Different Land Use Classes Using a Flow Model

Earth Systems and Environment ◽

10.1007/s41748-019-00141-w ◽

2019 ◽

Vol 4 (1) ◽

pp. 225-244 ◽

Cited By ~ 5

Author(s):

Md Abdullah Al Baky ◽

Muktarun Islam ◽

Supria Paul

Keyword(s):

Risk Assessment ◽

Critical Point ◽

Return Period ◽

Flood Risk ◽

Flood Hazard ◽

Flow Simulation ◽

Flood Risk Assessment ◽

Damage Functions ◽

Flood Vulnerability ◽

Different Levels

AbstractThis study is concerned with flood risk that can be assessed by integrating GIS, hydraulic modelling and required field information. A critical point in flood risk assessment is that while flood hazard is the same for a given area in terms of intensity, the risk could be different depending on a set of conditions (flood vulnerability). Clearly, risk is a function of hazard and vulnerability. This study aims to introducing a new approach of assessing flood risk, which successfully addresses this above-mentioned critical issue. The flood risk was assessed from flood hazard and vulnerability indices. Two-dimensional flood flow simulation was performed with Delft3D model to compute floodplain inundation depths for hazard assessment. For the purpose of flood vulnerability assessment, elements at risk and flood damage functions were identified and assessed, respectively. Then, finally flood risk was assessed first by combining replacement values assessed for the elements and then using the depth–damage function. Applying this approach, the study finds that areas with different levels of flood risk do not always increase with the increase in return period of flood. However, inundated areas with different levels of flood depth always increase with the increase in return period of flood. The approach for flood risk assessment adopted in this study successfully addresses the critical point in flood risk study, where flood risk can be varied even after there is no change in flood hazard intensity.

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Global Flood Model: Revolutionising Flood Catastrophe Modelling

10.5194/egusphere-egu2020-7632 ◽

2020 ◽

Author(s):

Paul Dunning ◽

Kirsty Styles ◽

Daniel Evans ◽

Stephen Hutchings

Keyword(s):

Risk Assessment ◽

Flood Risk ◽

Flood Hazard ◽

Insurance Industry ◽

Flood Risk Assessment ◽

Catastrophe Model ◽

Geographical Regions ◽

Flood Model ◽

Catastrophe Modelling ◽

Catastrophe Models

Catastrophe models are well established tools, traditionally used by the re/insurance industry to assess the financial risk to insured property (&#8220;exposure&#8221;) associated with natural perils. Catastrophe modelling is challenging, particularly for flood perils over large geographical scales, for a number of reasons. To adequately capture the fine spatial variability of flood depth, a flood catastrophe model must be of high spatial resolution. To validly compare estimates of risk obtained from catastrophe models for different geographical regions, those models must be built from geographically consistent data. To compare estimates of risk between any given collection of geographical regions globally, global coverage is required.Traditional catastrophe models struggle to meet these requirements; compromises are made, often for performance reasons. &#160;In addition, traditional models are typically static datasets, built in a discrete process prior to their use in exposure risk assessment. Scientific assumptions are therefore deeply embedded; there is little scope for the end user to adjust the model based on their own scientific knowledge.This research presents a new and better approach to catastrophe modelling that addresses these challenges and, in doing so, has allowed creation of the world&#8217;s first global flood catastrophe model.JBA&#8217;s Global Flood Model is facilitated by a technological breakthrough in the form of JBA&#8217;s FLY Technology. The innovations encoded in FLY have enabled JBA to create a model capable of consistent global probabilistic flood risk assessment, operating at 30m resolution and supported by a catalogue of 15 million distinct flood events (both river and surface water). FLY brings a model to life dynamically, from raw flood hazard data, simultaneously addressing the user configurability and performance challenges.Global Flood Model and FLY Technology will be of interest to those involved in financial, economic or humanitarian risk assessment, particularly in and between countries and regions not covered by flood catastrophe models to date. The detail of how they work will be covered here, and their power in facilitating consistent global flood risk assessment will be demonstrated.

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Available Flood Evacuation Time for High-Risk Areas in the Middle Reach of Chao Phraya River Basin

Water ◽

10.3390/w10121871 ◽

2018 ◽

Vol 10 (12) ◽

pp. 1871 ◽

Cited By ~ 5

Author(s):

Sarawut Jamrussri ◽

Yuji Toda

Keyword(s):

Risk Assessment ◽

River Basin ◽

Flood Risk ◽

Flood Hazard ◽

Flood Risk Assessment ◽

Design Flood ◽

Analytic Hierarchy ◽

Flood Risk Mapping ◽

Evacuation Plan ◽

Chao Phraya River

Information about risk is essential to design flood risk management programs. To our knowledge, this is the first attempt to develop an emergency flood evacuation plan based on flood risk assessment. Flood risk assessment in the middle Chao Phraya River Basin (CPRB) was simultaneously analyzed and mapped as the product of flood hazard, and social vulnerability maps generated by fuzzy Analytic Hierarchy Process (AHP) and fuzzy logic. One of the purposes of flood risk mapping is to promote proper and prompt evacuation actions for residents. The emergency flood evacuation model was tested to explore the available time of evacuation, to reduce the risk or even the loss of life. The simulation results showed that significant time was available for evacuation in the middle CPRB. This was calculated based on a physical status of evacuees, safe evacuation condition, shortest evacuation path, flood shelter, and road capacity.

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Towards dynamics in flood risk assessment

Natural Hazards and Earth System Science ◽

10.5194/nhess-12-3571-2012 ◽

2012 ◽

Vol 12 (11) ◽

pp. 3571-3587 ◽

Cited By ~ 25

Author(s):

B. Mazzorana ◽

L. Levaggi ◽

M. Keiler ◽

S. Fuchs

Keyword(s):

Risk Assessment ◽

Flood Risk ◽

Planning Process ◽

Cost Benefit Analysis ◽

Risk Mitigation ◽

Flood Hazard ◽

Mitigation Strategies ◽

Flood Risk Assessment ◽

Mountain Areas ◽

Flood Impacts

Abstract. As a consequence of flood impacts, communities inhabiting mountain areas are increasingly affected by considerable damage to infrastructure and property. The design of effective flood risk mitigation strategies and their subsequent implementation is crucial for a sustainable development in mountain areas. The assessment of the dynamic evolution of flood risk is the pillar of any subsequent planning process that is targeted at a reduction of the expected adverse consequences of the hazard impact. Given these premises, firstly, a comprehensive method to derive flood hazard process scenarios for well-defined areas at risk is presented. Secondly, conceptualisations of a static and dynamic flood risk assessment are provided. These are based on formal schemes to compute the risk mitigation performance of devised mitigation strategies within the framework of economic cost-benefit analysis. In this context, techniques suitable to quantify the expected losses induced by the identified flood impacts are provided.

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Climate Justice Planning in Global South: Applying a Coupled Nature–Human Flood Risk Assessment Framework in a Case for Ho Chi Minh City, Vietnam

Water ◽

10.3390/w13152021 ◽

2021 ◽

Vol 13 (15) ◽

pp. 2021

Author(s):

Chen-Fa Wu ◽

Szu-Hung Chen ◽

Ching-Wen Cheng ◽

Luu Van Thong Trac

Keyword(s):

Flood Risk ◽

Flood Hazard ◽

Climate Justice ◽

Ho Chi Minh City ◽

Flood Risk Assessment ◽

Urban Floods ◽

Flood Vulnerability ◽

Urban Flood ◽

Vulnerability Map ◽

The City

Developing countries in the global south that contribute less to climate change have suffered greater from its impacts, such as extreme climatic events and disasters compared to developed countries, causing climate justice concerns globally. Ho Chi Minh City has experienced increased intensity and frequency of climate change-induced urban floods, causing socio-economic damage that disturbs their livelihoods while urban populations continue to grow. This study aims to establish a citywide flood risk map to inform risk management in the city and address climate justice locally. This study applied a flood risk assessment framework integrating a coupled nature–human approach and examined the spatial distribution of urban flood hazard and urban flood vulnerability. A flood hazard map was generated using selected morphological and hydro-meteorological indicators. A flood vulnerability map was generated based on a literature review and a social survey weighed by experts’ priorities using the Fuzzy Delphi Method and Analytic Network Process. Vulnerability indicators including demographic characteristics, infrastructure, and land use patterns were used to generate a flood vulnerability map. The results illustrate that almost the entire central and northeastern parts of the city are at high flood risk, whereas the western part is at low flood risk. The findings have implications in urban planning via identifying risk hot spots in order to prioritize resources for mitigating hazards and enhancing community resilience to urban floods.

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