Increase In Flood Damage Research Articles

Residential flood risk in Metro Vancouver due to climate change using probability boxes

ABSTRACT To enhance the decision-making process and reduce economic losses caused by future flooding, it is critical to quantify uncertainty in each step of flood risk analysis. To address the often-missing uncertainty quantification, we propose a new methodology that combines damage functions and probability bounds analysis. We estimate the likely direct tangible damage to 375,973 residential buildings along the Fraser River through Metro Vancouver, Canada, for a range of climate change driven flood scenarios, while transparently representing the associated uncertainties caused by sampling error, imprecise measurement, and uncertainty in building height and basement conditions. Furthermore, for the purposes of developing effective management strategies, uncertainties in this study are classified into two categories, namely aleatory and epistemic. According to our findings and absent significant action, we should expect an enormous increase in flood damage to the four categories of residential buildings considered in this study by the year 2100. Moreover, the results show that second-order Monte Carlo simulation cannot adequately represent epistemic uncertainty for small sample sizes. In such a case, we recommend employing a probability box to delineate the epistemic uncertainty.

Application of Running Water-Type Retarding Basin to Old Kinu River Floodplain, Japan

In the upper and middle reaches of rivers in Japan, river channels used to meander in a comparatively narrow floodplain and heavy rain runoff used to naturally expand over the entire floodplain, retarding floods toward the downstream. Recent continuous levee building to prevent river overflow has had two kinds of negative effects, namely an increase in flood damage in areas of a floodplain closed by levees and river terraces at the time of runoff over the river channel capacity, and an increase in the flood peak toward the downstream. This study introduces the concept of a running water-type retarding basin that mitigates flood damage by allowing excess runoff to pass through the floodplain, restoring a natural hydrological process. After a description of the concept of the facility design, a design example is presented for a closed floodplain of the Kinu River Floodplain, where excess runoff caused severe flood damage in 2015, to quantify the performance and effects of the running water-type retarding basin.

The effect of flood experience on public preferences for land preservation: evidence from referendum votes

In response to losses of open space, local open space referenda have become a popular means for land preservation in the U.S. This study is the first to empirically examine the relationship between flood experience and voter support for open space referenda. We collect data on open space referenda between 2001 to 2015 from the Trust for Public Land’s (TPL) LandVote database. Flood occurrence and damage data are derived from the Spatial Hazard Events and Losses Database for the United States (SHELDUS) database. Our findings suggest that voters become less supportive of subsequent open space ballot measures if their communities recently experienced a flood event. Our preferred specification indicates that a flood would decrease the odds of a ‘yes’ vote by about 7.5%. If we use flood damage data to measure disaster impacts, our results show that a 10% increase in flood damage is expected to decrease the odds of a ‘yes’ vote by about 6%. These findings are consistent with recent experimental research showing that disaster exposure has a negative effect on preferences for local public good investments.

SWOT PRINCIPLE IN FLOOD RISK MANAGEMENT

An analysis of global statistics shows a substantial increase in flood damage over the past few decades. With the recent transition to a more risk-based approach in European flood management policy, flood analysis models have become an important part of flood risk management. In many cases, flood damages are extensive to the environment, to the economy and also socially. According to the priority development trend "Infrastructure and Environment", Ungheni district of Republic of Moldova (RM) aims for an efficient infrastructure, based on environmental protection, whose development, operation and maintenance will be done using of a database, protocols, existing guides and accessible to the level of each local public administration. In the last decade, projects have been implemented in Moldova to study the phenomenon of floods in order to develop structural and non-structural measures to protect localities. This article aims is to systematize the existing knowledge and characteristics of the methods available to give operational recommendations and principles that can support authorities, local entities, and the stakeholders involved in decision-making with regard to flood risk management in their compliance with the Floods Directive (2007/60/EC), national and local legal framework.

Analysis of disaster resilience of urban planning facilities on urban flooding vulnerability

Rainfall continues to increase due to the influence of global warming and is resulting in an increase in flood damage. The purpose of this study is to propose an approach for reducing urban flood damage and improving urban resilience. Urban flooding vulnerability analysis used land use and building characteristics as evaluation indicators. Disaster resilience analysis of urban planning facilities focused on urban and spatial aspects. The results of these analyses were overlapped to analyze whether urban planning facilities were properly located in areas vulnerable to urban flooding. The result of mapping the two results showed that there are some urban planning facilities with low resilience in the Red Zone, the central commercial area of Changwon, which has the highest vulnerability. This zone should have the appropriate placement of high-resilience facilities, such as disaster prevention facilities and space facilities. This study proposes a method to minimize flood damage in urban space. This system can cope with and systematically manage flood damage by increasing disaster resilience through appropriate land use planning and site selection for urban planning facilities.

Lessons learned from applying adaptation pathways in flood risk management and challenges for the further development of this approach

Worldwide, an increase in flood damage is observed. Governments are looking for effective ways to protect lives, buildings, and infrastructure. At the same time, a large investment gap seems to exist—a big difference between what should necessarily be done to curb the increase in damage and what is actually being done. Decision-makers involved in climate adaptation are facing fundamental (so-called deep) uncertainties. In the course of time, the scientific community has developed a wide range of different approaches for dealing with these uncertainties. One of these approaches, adaptation pathways, is gaining traction as a way of framing and informing climate adaptation. But research shows that “very little work has been done to evaluate the current use of adaptation pathways and its utility to practitioners and decision makers” (Lin et al. 2017, p. 387). With this paper, the authors, as action researchers and practitioners involved in two of the world’s largest real-life applications of this approach in flood risk management, aim to contribute to filling in that gap. Analysis of the experience in the United Kingdom and the Netherlands in long-term planning in flood risk management shows that the adaptation pathways approach is effective in keeping decision processes going forward, to the final approval of a long-term plan, and helps increase awareness about uncertainties. It contributes to political support for keeping long-term options open and motivates decision-makers to modify their plans to better accommodate future conditions. When it comes to implementing the plans, there are still some major challenges, yet to be addressed, amongst others: the timely detection of tipping points in situations with large natural variability, the inclusion of measures that prepare for a switch to transformational strategies, and the retention of commitment of regional and local authorities, non government organizations, and the private sector, to climate adaptation as national policies move from blueprint planning to adaptive plans. In delivering this feedback, the authors hope to motivate the scientific community to take on these challenges.

Predictability of state-level flood damage in the conterminous United States: the role of hazard, exposure and vulnerability

Understanding historical changes in flood damage and the underlying mechanisms is critical for predicting future changes for better adaptations. In this study, a detailed assessment of flood damage for 1950–1999 is conducted at the state level in the conterminous United States (CONUS). Geospatial datasets on possible influencing factors are then developed by synthesizing natural hazards, population, wealth, cropland and urban area to explore the relations with flood damage. A considerable increase in flood damage in CONUS is recorded for the study period which is well correlated with hazards. Comparably, runoff indexed hazards simulated by the Variable Infiltration Capacity (VIC) model can explain a larger portion of flood damage variations than precipitation in 84% of the states. Cropland is identified as an important factor contributing to increased flood damage in central US while urbanland exhibits positive and negative relations with total flood damage and damage per unit wealth in 20 and 16 states, respectively. Overall, flood damage in 34 out of 48 investigated states can be predicted at the 90% confidence level. In extreme cases, ~76% of flood damage variations can be explained in some states, highlighting the potential of future flood damage prediction based on climate change and socioeconomic scenarios.

Development of model for the estimation of direct flood damage including the movable property

In recent decades, an increase in flood damage has been observed; therefore, the assessment of potential damage is becoming more important. Estimation of potential flood damage can be achieved with various existing models. However, their transferability is questionable and the actual availability of input data is often limited. To overcome these shortcomings, a new model has been developed to effectively estimate flood damage in Croatia. The proposed model uses only publicly available data such as the CORINE data set and information from censuses. The model was developed in an open source Geographic Information System programme. Validation of the model's performance was performed using data from the extreme May 2014 flood that occurred in the Balkan Peninsula. Furthermore, the model has already been used in practice and has proven to be user‐friendly due to the minimum input required from open source data, allowing for insights to be gained from data updates.

Mesoscale extreme rainfall events in West Africa: The cases of Niamey (Niger) and the Upper Ouémé Valley (Benin)

Abstract In West Africa, a sharp decrease in rainfall has occurred in conjunction with an increase in flood damage since 1970. The material damage and loss of life resulting from floods highlights the undeniable vulnerability of populations to this threat and illustrates the importance of addressing the evolution of hazardous precipitation caused by intense rainstorms. This work aims to improve our knowledge of the behaviour of extreme rainfall in West Africa by studying the sub-hourly, hourly and daily evolution of the most extreme rainfall events, a topic that is especially important to those interested in studying the links between heavy rainfall and flash flooding or inundation. This study analyses the classes of extreme rainfall events in two distinct climatic areas within West Africa using the meteorological scales relevant to rainfall processes. The study is based on two precipitation datasets recorded by dense networks of rain gauges set up within the meso-sites of Niamey (Niger, Sahelian area) and the Upper Oueme Valley (Northern Benin, Soudanian zone) from 2000 to 2010 and 1998 to 2010, respectively. The Gumbel distribution was used to analyse the frequency of the maximum rainfall series for durations varying from 5 min to 24 h. The reliability of this model was examined, and the Intensity-Density-Frequency (IDF) curves derived from it were used to estimate the critical rainfall intensities at each site. The results returned exceeded frequencies that were useful for the isolation and classification of extreme rainfall cases using temporal characteristics. The climatological results confirm the existence of a latitudinal gradient in the mean annual rainfall and number of extreme events at the mesoscale. The classification methods illustrate clear distinctions between local, meso and synoptic scale events derived from convective systems over the Sahel. In contrast, Soudanian climate conditions lead to a nesting of the phenomena involved in the formation of cloud systems, making it difficult to classify rain events in that area. However, we were able to utilize the duration of rainfall events within this zone to discriminate between types of convective systems that cause extreme rainfall. For both areas, the proportion of precipitation in an extreme event compared to total yearly precipitation served as a suitable additional criterion used to objectively identify extreme precipitation event types.

Collaborative Strategies for Sustainable EU Flood Risk Management: FOSS and Geospatial Tools—Challenges and Opportunities for Operative Risk Analysis

An analysis of global statistics shows a substantial increase in flood damage over the past few decades. Moreover, it is expected that flood risk will continue to rise due to the combined effect of increasing numbers of people and economic assets in risk-prone areas and the effects of climate change. In order to mitigate the impact of natural hazards on European economies and societies, improved risk assessment, and management needs to be pursued. With the recent transition to a more risk-based approach in European flood management policy, flood analysis models have become an important part of flood risk management (FRM). In this context, free and open-source (FOSS) geospatial models provide better and more complete information to stakeholders regarding their compliance with the Flood Directive (2007/60/EC) for effective and collaborative FRM. A geospatial model is an essential tool to address the European challenge for comprehensive and sustainable FRM because it allows for the use of integrated social and economic quantitative risk outcomes in a spatio-temporal domain. Moreover, a FOSS model can support governance processes using an interactive, transparent and collaborative approach, providing a meaningful experience that both promotes learning and generates knowledge through a process of guided discovery regarding flood risk management. This article aims to organize the available knowledge and characteristics of the methods available to give operational recommendations and principles that can support authorities, local entities, and the stakeholders involved in decision-making with regard to flood risk management in their compliance with the Floods Directive (2007/60/EC).

Contribution of land use changes to future flood damage along the river Meuse in the Walloon region

Abstract. Managing flood risk in Europe is a critical issue because climate change is expected to increase flood hazard in many european countries. Beside climate change, land use evolution is also a key factor influencing future flood risk. The core contribution of this paper is a new methodology to model residential land use evolution. Based on two climate scenarios ("dry" and "wet"), the method is applied to study the evolution of flood damage by 2100 along the river Meuse. Nine urbanization scenarios were developed: three of them assume a "current trend" land use evolution, leading to a significant urban sprawl, while six others assume a dense urban development, characterized by a higher density and a higher diversity of urban functions in the urbanized areas. Using damage curves, the damage estimation was performed by combining inundation maps for the present and future 100 yr flood with present and future land use maps and specific prices. According to the dry scenario, the flood discharge is expected not to increase. In this case, land use changes increase flood damages by 1–40%, to €334–462 million in 2100. In the wet scenario, the relative increase in flood damage is 540–630%, corresponding to total damages of €2.1–2.4 billion. In this extreme scenario, the influence of climate on the overall damage is 3–8 times higher than the effect of land use change. However, for seven municipalities along the river Meuse, these two factors have a comparable influence. Consequently, in the "wet" scenario and at the level of the whole Meuse valley in the Walloon region, careful spatial planning would reduce the increase in flood damage by no more than 11–23%; but, at the level of several municipalities, more sustainable spatial planning would reduce future flood damage to a much greater degree.

The Role of Insurance in Managing Natural Hazard Risks: Private Versus Social Decisions

We explore the interaction between individual and collective decisions concerning natural hazards. Collective actions such as building a dam change the risks faced by private individuals. We show that, with proper incentives, individual reactions to such changes in risk can serve to enhance risk management by utilizing individual's decisions to take account of their specialized knowledge about their risk preferences and losses. We demonstrate that the efficient response to construction of a dam may be private actions that lead to a fully anticipated increase in flood damage. In such instances, zoning that focuses on reducing flood damage may lead to less efficient use of the flood plain. More generally, even where incentives for underinvestment in market insurance and self‐insurance are present, constraining use of the flood plain by zoning will not generally lead to efficient outcomes. The model identifying conditions under which informed individuals have the incentives to make efficient decisions is powerful and directs attention toward more fruitful approaches.

The Floodplain and the Seashore: A Comparative Analysis of Hazard-Zone Occupance

HE United States is in danger today of embarking on a large-scale and costly program of coastal defense against storm hazard comparable with the program of flood control that has been operating in river valleys for the past quarter of a century. Federal legislation passed in 1936, and subsequently, has been largely the reason for the heavy investment in flood-control engineering works, to the neglect of possible alternatives. Yet appraisals of the flood-control program are in general agreement that despite federal expenditures of about five billion dollars, average annual damages from floods have continued to rise.' Nor is a brighter prospect held for the future. The Chief of Engineers stated in 1960 that at the present rate of expenditure flood protection will 'just about keep up with the increase in flood damage that may be anticipated by 1980 as a result of flood plain development over the next two decades.2 A repetition of the same course of action with respect to coastal flood problems seems likely. The storm of March 5-8, 1962,3 on the east coast of the United States (Fig. 1) focused attention on coastal storm damage. One informed official recently remarked that it seems unlikely Congress will be satisfied that it has done its duty by coastal constituents until an Atlantic Wall has been built from Maine to Mexico!