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Floods have been identified as the most frequent and threatening disaster in Sri Lanka amidst an increasing trend of natural and man-made disasters in the world. Subject experts state that disaster risk management should be based on the results of risk assessments, but flood risk management in Sri Lanka is seemingly not based on community-level flood risk assessments. Accordingly, the purpose of this paper is to introduce a community-level flood risk assessment method to the local context of Sri Lanka.

The sample (n = 425) for the study was selected using the stratified random sampling method, and the Deduru Oya basin was selected as the study area. The risk assessment model introduced by Bollin et al. (2003) was used for the current study, but with some modifications. Accordingly, 16 variables were selected for the risk assessment. Descriptive data analysis methods were used in the study.

Community-level flood risk assessment method was introduced. Variable index, flood risk index and flood risk map were developed for the study area. The Grama Niladari Divisions (GNDs) were grouped into five categories from very high risk to very low risk. The GNDs named Wirakumandaluwa, Thimbilla, Deduru Oya, Bangadeniya and Elivitiya were ranked as the most flood-risk GNDs, respectively.

This paper produces a flood risk assessment method for the local context. Flood risk in the study area was assessed based on people’s perceptions. Accordingly, the flood risk index and flood risk map for the study area were developed based on the empirical data. GNDs were ranked based on the flood risk index.

In effort to understand and reduce flood consequences more effectively and strategically, flood risk assessment has been a cornerstone of a long-term flood management. One component of flood risk assessment is the estimation of a range of possible damage to an area exposed to flooding, that is, the vulnerability curve. The vulnerability curve can be depicted by a stage–damage relationship. This study attempts to investigate how vulnerability to flooding can be quantitatively assessed using a micro-scale approach in Malaysia’s vulnerable areas. A residential area in Kota Bharu was chosen as the case study area. Depth–damage relationships from a multiple regression function of Department of Irrigation and Drainage Malaysia and spatial variability of residential buildings were used for the micro-scale assessment. Final estimates of expected annual damage were then calculated for each building type at 1-, 3- and 5-day flood durations. Results show that the methodology adopted is feasible to be applied for local-scale assessment flood risk assessment in Malaysia. The results also suggest that applying the methodology is possible when given wider availability of resources and information. This is particularly important for a robust end-to-end flood risk assessment for long-term effective flood management in Malaysia.

Nowadays, under climate change contexts, natural disasters are becoming stronger in intensity and probability. The impacts of natural disasters on people and the environment are also getting worse. The purpose of this study was conducted to provide a method of assessing disaster risks, in particular, floods for human life in Mid Central Vietnam.

The pre-disaster assessment method was used based on the analysis of hazard factors (Hazard-H), exposure to hazards (Exposure-E) and vulnerability (Vulnerability-V).

Flood disaster risks in the area are assessed and displayed on spatial maps. The districts in coastal plains of Quang Ngai and Thua Thien Hue provinces have the highest levels of risk. These assessments will play an important role in supporting flood prevention and mitigation in the region.

According to the authors, this is the first study assessing the flood risk in Vietnam on the pre-disaster perspective. The assessment provides a plain point of view on natural disaster impacts that supporting disaster prevention services.

The purpose of this paper was to develop an integrated framework for assessing the flood risk and climate adaptation capacity of an urban area and its critical infrastructures to help address flood risk management issues and identify climate adaptation strategies.

Using the January 2011 flood in the core suburbs of Brisbane City, Queensland, Australia, various spatial analytical tools (i.e. digital elevation modeling and urban morphological characterization with 3D analysis, spatial analysis with fuzzy logic, proximity analysis, line statistics, quadrat analysis, collect events analysis, spatial autocorrelation techniques with global Moran’s I and local Moran’s I, inverse distance weight method, and hot spot analysis) were implemented to transform and standardize hazard, vulnerability, and exposure indicating variables. The issue on the sufficiency of indicating variables was addressed using the topological cluster analysis of a two-dimension self-organizing neural network (SONN) structured with 100 neurons and trained by 200 epochs. Furthermore, the suitability of flood risk modeling was addressed by aggregating the indicating variables with weighted overlay and modified fuzzy gamma overlay operations using the Bayesian joint conditional probability weights. Variable weights were assigned to address the limitations of normative (equal weights) and deductive (expert judgment) approaches. Applying geographic information system (GIS) and appropriate equations, the flood risk and climate adaptation capacity indices of the study area were calculated and corresponding maps were generated.

The analyses showed that on the average, 36 (approximately 813 ha) and 14 per cent (approximately 316 ha) of the study area were exposed to very high flood risk and low adaptation capacity, respectively. In total, 93 per cent of the study area revealed negative adaptation capacity metrics (i.e. minimum of −23 to <0), which implies that the socio-economic resources in the area are not enough to increase climate resilience of the urban community (i.e. Brisbane City) and its critical infrastructures.

While the framework in this study was obtained through a robust approach, the following are the research limitations and recommended for further examination: analyzing and incorporating the impacts of economic growth; population growth; technological advancement; climate and environmental disturbances; and climate change; and applying the framework in assessing the risks to natural environments such as in agricultural areas, forest protection and production areas, biodiversity conservation areas, natural heritage sites, watersheds or river basins, parks and recreation areas, coastal regions, etc.

This study provides a tool for high level analyses and identifies adaptation strategies to enable urban communities and critical infrastructure industries to better prepare and mitigate future flood events. The disaster risk reduction measures and climate adaptation strategies to increase urban community and critical infrastructure resilience were identified in this study. These include mitigation on areas of low flood risk or very high climate adaptation capacity; mitigation to preparedness on areas of moderate flood risk and high climate adaptation capacity; mitigation to response on areas of high flood risk and moderate climate adaptation capacity; and mitigation to recovery on areas of very high flood risk and low climate adaptation capacity. The implications of integrating disaster risk reduction and climate adaptation strategies were further examined.

The newly developed spatially explicit analytical technique, identified in this study as the Flood Risk-Adaptation Capacity Index-Adaptation Strategies (FRACIAS) Linkage/Integrated Model, allows the integration of flood risk and climate adaptation assessments which had been treated separately in the past. By applying the FRACIAS linkage/integrated model in the context of flood risk and climate adaptation capacity assessments, the authors established a framework for enhancing measures and adaptation strategies to increase urban community and critical infrastructure resilience to flood risk and climate-related events.

The overall objective of this study is envisaged to provide decision makers with actionable insights and access to multi-risk maps for the most in-danger stave churches (SCs) among the existing 28 churches at high spatial resolution to better understand, reduce and mitigate single- and multi-risk. In addition, the present contribution aims to provide decision makers with some information to face the exacerbation of the risk caused by the expected climate change.

Material and data collection started with the consultation of the available literature related to: (1) SCs' conservation status, (2) available methodologies suitable in multi-hazard approach and (3) vulnerability leading indicators to consider when dealing with the impact of natural hazards specifically on immovable cultural heritage.

The paper contributes to a better understanding of place-based vulnerability with local mapping dimension also considering future threats posed by climate change. The results highlight the danger at which the SCs of Røldal, in case of floods, and of Ringebu, Torpo and Øye, in case of landslide, may face and stress the urgency of increasing awareness and preparedness on these potential hazards.

The contribution for the first time aims to homogeneously collect and report all together existing spread information on architectural features, conservation status and geographical attributes for the whole group of SCs by accompanying this information with as much as possible complete 2D sections collection from existing drawings and novel 3D drawn sketches created for this contribution. Then the paper contributes to a better understanding of place-based vulnerability with local mapping dimension also considering future threats posed by climate change. Then it highlights the danger of floods and landslides at which the 28 SCs are subjected. Finally it reports how these risks will change under the ongoing impact of climate change.

Risk assessment is imperative for disaster risk reduction. The risk is rooted to various physical, social, economic, demographic and environmental factors that determine the probable magnitude of loss during an extreme event. By way of bringing a conceptual model into practice, this paper aims to examine the flood risk of the Srinagar city.

The “risk triangle” model has been adopted in the present investigation evaluating parameters, reflective of hazard (intensity), exposure (spatial) and vulnerability (sensitivity) using Landsat-8 operational land imager scene (10 September 2014), global positioning system, Cartosat-1 digital elevation model and socioeconomic and demographic data (Census of India, 2011). The authors characterise flood hazard intensity on the basis of variability in water depth during a recent event (September 2014 Kashmir flood); spatial exposure as a function of terrain elevation; and socioeconomic structure and demographic composition of each municipal ward of the city as a determinant factor of the vulnerability. Statistical evaluation and geographic information system-based systematic integration of all the multi-resolution data layers helped to develop composite flood risk score of each ward of the city.

Principal deliverable of this study is flood risk map of the Srinagar city. The results reveal that approximately 46 per cent of the city comprising 33 municipal wards is at high risk, while rest of the area, i.e. 17 and 37 per cent, exhibit moderate and low levels of risk, constituting 23 and 12 municipal wards, respectively. It is very likely that the municipal wards expressing high risk may witness comparatively more damage (impact) during any future flood event. Thus, there is a need of planned interventions (structural and non-structural) to minimise the emergent risk.

Very rare attempts have been made to bring theoretical models of disaster research in practice; this is mainly because of the complexities associated with the data (selection, availability and subjectivity), methodology (integration, quantification) and resolution (spatial scales). In this direction, this work is expected to have considerable impact, as it provides a clear foundation to overcome such issues for the studies aiming at disaster risk assessment. Furthermore, using varied primary and secondary data, this paper demonstrates the relative (municipal wards) flood risk status of the Srinagar city, which is one of the key aspects for flood hazard mitigation.

In Kumamoto, Japan flood risk information is made available on several websites. In the event of heavy rainfall, local citizens need to access these websites and make household-level decisions. It is difficult for citizens to monitor all these sites, analyze and make effective decisions. Evacuation orders are issued by the local government who then filters the information to the relevant multiple stakeholders and local citizens. This takes time and reduces the response lead time of citizens especially in fast-onset floods. There was a therefore a need for illustrative integrated approaches, integrating these data sets.

Using precipitation, river water and tide level data, user-friendly real-time graphs were set up for the Shirakawa River, Kumamoto, Japan. Flood data were collected and used to create numerical simulations, and electronic community-based hazard maps were created.

The data gathered from the July 2012 flood event were used as a demonstrator, illustrating a flood event, as well as how to utilize the information provided on user-friendly real-time graphs’ website, to determine the location, future time and possibility of flooding. Additionally, an electronically generated flood hazard map-making process was developed for distribution across Japan.

These illustrative approaches are relatively new and have only been tested and evaluated in communities across Kumamoto, Japan. As such, it is too early to determine robustness and generalized applications worldwide, especially in data-scarce countries and communities. Improvements and maintenance are ongoing.

These illustrative approaches can be adopted and utilized in cities and communities around the globe, thereby helping in overall disaster risk-reduction initiatives and better flood risk management strategies.

These illustrative approaches are new to Kumamoto City and Japan. These provide citizens with user-friendly real-time graphs that can be accessed anytime and used in flood hazard preparations, warnings, response or recovery.

Understanding risk is more than just modeling risk; it requires an understanding of the development and social processes that underlie and drive the generation of disaster risk. Here, in addition to a review of more technical factors, this paper aims to discuss a variety of institutional, social and political considerations that must be managed for the results of a risk assessment to influence actions that lead to reductions in natural hazard risk.

The technical approaches and the institutional, social and political considerations covered in this paper are based on a wide range of experiences gleaned from case studies that touch on a variety of activities related to assessing the risks and impacts of natural hazards, and from the activities of the World Bank’s Global Facility for Disaster Reduction and Recovery.

Risk information provides a critical foundation for managing disaster risk across a wide range of sectors. Appropriate communication of robust risk information at the right time can raise awareness and trigger action to reduce risk. Communicating this information in a way that triggers action requires an understanding of the developments and social processes that underlie and drive the generation of risk, as well as of the wider Disaster Risk Management (DRM) decision-making context.

Prior to the initiation of a quantitative risk assessment one should clearly define why an assessment is needed and wanted, the information gaps that currently prevent effective DRM actions and the end-users of the risk information. This requires developing trust through communication among the scientists and engineers performing the risk assessment and the decision-makers, authorities, communities and other intended users of the information developed through the assessment.

This paper summarizes the technical components of a risk assessment as well as the institutional, social and political considerations that should be considered to maximize the probability of successfully reducing the risk defined by a risk assessment.

The purpose of this paper is to introduce a geospatial approach for buildings flood vulnerability assessment using an indicator-based method (IBM) to support flood risk assessment and mapping of physical elements at risk in Kota Bharu District, Kelantan, Malaysia.

The study developed an indicator-based approach to undertake physical flood vulnerability assessment of buildings. The approach takes into consideration flood hazard intensity, building characteristics and structures surrounding the environment as factors that influence flood vulnerability. The aggregation of the total flood vulnerability index is carried out in a geographic information system (GIS) environment.

The results provide a spatial representation of buildings flood vulnerability index in Kota Bharu Malaysia, and the degree of expected vulnerability is expressed on a scale between 0 to 1 (low damage to total damage). Mapping flood vulnerability index of buildings should be considered in future flood mitigation and evacuation planning.

Unlike other indicator-based methods (IBMs) developed for physical flood vulnerability assessment, in the current study, hazard intensity has been considered and incorporated in the physical flood vulnerability model.

The government-led public healthcare services in Sri Lanka became a major strength in managing the COVID-19 comparatively well. However, natural hazards are a major threat to this healthcare system, as they cause severe damages, especially to curative healthcare infrastructures such as hospitals. Floods have been the major contributor to the economic loss of the Sri Lankan healthcare system. Therefore, the purpose of this study is to develop a proper flood risk assessment framework for Sri Lankan hospitals.

This research study has attempted to develop a flood vulnerability assessment tool for hospitals using the concept of Depth Damage Functions (DDFs). Flood vulnerability curves have been developed for identified critical units of hospitals considering the damage caused to building contents which are predominantly expensive medical equipment. The damage caused only by wetting was considered in generating vulnerability curves. Structured interviews were conducted with government officials in the healthcare sector to gather details on the cost and damages of medical equipment. Pilot studies were carried out in two hospitals identified as located in flood-prone areas and have previous experiences of flooding, to acquire data regarding building contents of the critical units.

The developed vulnerability curves indicate that no major damage would occur to building contents in critical units (other than the labor room) until the inundation depth reaches a value of 0.6–0.9 m (varies for each type of unit). It is also noteworthy that after a certain range in the inundation depth, the damage increases drastically, and building contents would incur total damage if the inundation depth passes a value of 1.2–1.5 m.

This study explains the initial phase of developing a flood vulnerability assessment framework for Sri Lankan hospitals. Not many studies had been carried out to assess the vulnerability of hospitals specifically for floods using vulnerability curves. The study recommends a zoning system with pre-defined vulnerability levels for critical units during a flood, which can be associated with evacuation planning as well. Further studies must be carried out to verify this system for hospitals in Sri Lanka.