Changes in transport accessibility as a result of flooding: a case study of the Mazovia Province (Eastern Poland)

This paper presents the results of research investigating the impact of flooding on the temporal aspect of transport accessibility at national, regional and local levels in the Mazovia Province – an administrative region in Poland. For the purposes of this study the authors measured the theoretical journey times by private transport between settlement units for two variants: journeys made under normal circumstances, that is, without a flood; and journeys made during a flood event, which would necessitate diversions to avoid flooded road sections. This allowed the theoretical journey time differences to be calculated. It was assumed that vehicles move at the highest permissible speed along routes allowing the shortest travel times. The methods of accessibility assessment employed in this paper are based on distance measurements and use isochrones and a cumulative approach. Analysis carried out by the authors has shown that for interregional, intraregional and local journeys, the flooding of a part of the Mazovia region results in changes in travel times, but their absolute and relative magnitudes vary widely. It was found that in the case of national scale journeys the majority of relative journey time increases were no greater than three times the normal duration, while on a local scale they do not exceed 75%. For areas with a high risk of flooding there should be obligatory analyses of changes in transport accessibility; this would facilitate effective flood risk management. Appropriate traffic management in crisis situations would facilitate emergency and rescue services and help inhabitants and any other persons in flooded areas.     

中国洪涝灾害结构式与非结构式减灾措施耦合协调性研究

结构式与非结构式减灾措施是构成洪涝灾害防治体系的两个相互补充、相互促进的子系统,基于2008—2018年的面板数据,构建中国洪涝灾害结构式与非结构式减灾措施耦合协调度评价指标体系,引入耦合协调度模型测度中国洪涝灾害结构式与非结构式减灾措施建设水平以及两者间的耦合度和耦合协调度,以期进一步提升我国洪涝灾害防治体系的防灾减...     

长江荆江分蓄洪区历史演变、前景和风险管理

依据社会经济统计数据、水文资料、遥感影像信息和实地调查资料，分析了荆江分蓄洪区在历史演变过程中形成的分洪与发展的矛盾及其在未来长江流域防洪体系中的重要作用，指出其风险管理的必要性。运用基于GIS栅格数据的二维水动力洪水动态演进模型，对荆江分蓄洪区1954年的分洪过程进行了模拟和验证，模拟了不同分洪规划方案下的洪水淹没范围，水深和水位，并结合现阶段社会经济发展情况，定量估算了农户和农业的分洪可能损失。在分洪损失评估基础上提出了荆江分蓄洪区引导人口合理发展、促进土地有效利用、开展防洪教育、实施洪水保险和确保安全运用预案等减轻洪水损失提高运用机率的洪水风险管理初步方案。     

洪水灾害间接经济损失评估研究进展

受全球气候变化及人类活动的影响,洪水灾害发生的频率和损失越来越大,洪灾直接经济损失评估研究不断深入,但是,洪灾间接经济损失评估研究相对薄弱。为了能综合地对洪水灾害间接经济损失进行科学的评价,回顾了国内外洪水灾害间接经济损失评估的研究现状,综述了洪水灾害间接经济损失的内涵及组成(减产停产损失、产业关联损失和投资溢价损失),分析了他们之间的关系及相应的评估方法特点。指出洪水灾害间接经济损失主要指产业关联损失,投入产出法是间接经济损失评估的适用方法,但该方法的使用必须作适应性改进,上述观点可供洪灾间接经济损失评价参考。     

江苏省里下河腹部地区防洪效益计算

通过建立特定工程条件下洪涝淹没面积与水文特性之间的相关关系，并合理确定单位面积资产值和洪灾综合财产损失率，提出了防洪效益计算的一种简易可行的方法，并在里下河腹部地区进行了实际应用。     

Local perception of infrequent,extreme upland flash flooding: prisoners of experience?

The United Kingdom has experienced several exceptional summer flash floods in recent years and there is growing concern about the frequency of such events and the preparedness of the population. This paper uses a case study of the upper Ryedale flash flood (2005) and questionnaire and interview data to assess local perceptions of upland flash flooding. Experience of a major flash flood may not be associated with increased flood risk perception. Despite local residents’ awareness of a trend towards wetter summers and more frequent heavy rainfall, the poor maintenance of rivers was more frequently thought to be a more significant factor influencing local flood risk than climate change. Such findings have important implications for the potential success of contemporary national flood policies, which have put greater emphasis on public responsibility for responding to flooding. This study recommends, therefore, the use of fresh participatory approaches to redistribute and raise awareness of locally‐held flood knowledge.     

Influence of road characteristics on flood fatalities in Australia

ABSTRACT

An analysis of published flood fatalities in Australia occurring between 1960 and 2015 revealed that 49% of 229 flood fatalities were vehicle related. After reviewing previous work on vehicle-related flood fatalities, this study examines attributes of roadways that may have influenced driver decisions to enter floodwaters and the survivability of people in vehicles that did so and concludes by discussing policy implications. Characteristics most frequently present were small upstream catchment length that may influence the rate of rise of floodwaters; the absence of roadside barricades; deep flooding immediately adjacent to the roadway; the absence of lighting; dipping road grades that lead floodwaters to increase once a vehicle enters them; the lack of curb and guttering and the inability of motorists to easily turn around. Each of these factors were observed in at least 50% of the cases studied and provide a risk-based means of assessing other sites vulnerable to flooding but where fatalities have not been observed to date.     

Pai洲湾‘98决堤情况典型调查

１９９８年８月１日,湖北省嘉鱼县Ｐａｉ洲湾堤失事溃决,造成生大损失。调查表明,受大堤保护的Ｐａｉ洲湾居民防洪意识淡薄,多认为大堤不会失事。溃堤后,区内居民,尤其是溃口附近的一些居民采取的避洪行为不当,致命人员伤亡严重。这些问题在其他受防洪工程的地区同样存在。加强洪水知识和宣传,提高洪水风险区居民的防洪意识,是减轻洪水灾害的主要工作之一。     

中国与荷兰洪水风险分析方法的比较研究

基于洪水风险的定义,从洪灾发生概率、洪灾后果评估、风险评价指标和防洪标准经济优化决策原则等方面阐述了中荷两国在洪水风险分析研究方面的异同,初步分析了存在差别的原因以及两种方法的特点.在分别应用中国和荷兰现有风险评估方法分析安庆市堤防圈的洪水风险的基础上,探讨了将两国的风险分析方法进行整合的思路.算例表明,将堤防的工程风险与洪水本身出现的水文风险相结合,并考虑在不同洪水位下损失的差异的方法是与洪灾发生机理相符,综合考虑了各种不确定因素的、切合我国洪灾特点的一种值得进一步深入研究的新方法.     

Insurance and flood risk reduction in Ghana: do insurers penalise homeowners who take precautionary measures?

Today, many advocate insurance as a tool for coping with natural disasters. Beyond providing prompt financial relief to victims of disasters, insurance can also incentivise individuals to invest in preventive measures if insurers reward such efforts with reduced premiums. However, insurers might be unable to reward investments in precautionary measures with lower premiums if they are ill-informed about individual-level risks. Here, we explore how Ghanaian home insurers respond to investments in flood risk reduction by asking them to quote premiums for four identical buildings; two had investments in flood risk reduction, while the other two had none. We find that insurers did not reward investments in risk reduction, with some charging higher premiums for elevated buildings, suggesting they have interpreted such preventive measures as a sign of high flood risk. This failure to reward investments in precautionary measures may discourage insured homeowners from investing in risk reduction.     

Valuing floodplain protection and avoidance in a coastal watershed

Flood‐related losses in the United States are increasing despite large‐scale mitigation efforts. To offset the rising cost of floods, the US Congress passed legislation in 2014 that will augment insurance premiums to make the National Flood Insurance Program more actuarially sound. Consequently, there is interest in lowering flood‐related costs to the homeowner, both in terms of premiums and damage. This study addresses the issue by integrating premium savings and damages avoided based on several mitigation scenarios. Specifically, it examines how much policyholders within a watershed near Houston, Texas, could have saved between 1999 and 2009 had their communities introduced specific avoidance‐based mitigation activities. The results indicate that homeowners and communities can offset premium rises and a majority of the damage suffered through marginal expansions of such initiatives. However, the costs associated with their implementation could counter some of these savings, and hence they need to be considered in future work.     

Identifying the impact of the built environment on flood damage in Texas

Floods continue to pose the greatest threat to the property and safety of human communities among all natural hazards in the United States. This study examines the relationship between the built environment and flood impacts in Texas, which consistently sustains the most damage from flooding of any other state in the country. Specifically, we calculate property damage resulting from 423 flood events between 1997 and 2001 at the county level. We identify the effect of several built environment measures, including wetland alteration, impervious surface, and dams on reported property damage while controlling for biophysical and socio-economic characteristics. Statistical results suggest that naturally occurring wetlands play a particularly important role in mitigating flood damage. These findings provide guidance to planners and flood managers on how to alleviate most effectively the costly impacts of foods at the community level.     

An analysis of the causes and circumstances of flood disaster deaths

The objective of this paper is to investigate and to improve understanding of the causes and circumstances of flood disaster deaths. A standardised method of classifying flood deaths is proposed and the difficulties associated with comparing and assessing existing information on flood deaths are discussed. Thirteen flood cases from Europe and the United States, resulting in 247 flood disaster fatalities, were analysed and taken as indicative of flood disaster deaths. Approximately two-thirds of the deaths occurred through drowning. Thus, a substantial number of flood disaster fatalities are not related to drowning. Furthermore, males are highly vulnerable to dying in floods and unnecessary risk-taking behaviour contributes significantly to flood disaster deaths. Based on these results, recommendations are made to prevent loss of life in floods. To provide a more solid basis for the formulation of prevention strategies, better systematic recording of flood fatalities is suggested, especially those caused by different types of floods in all countries.     

Mitigating flood risk and enhancing community resilience to natural disasters: plan quality matters

In response to increasingly frequent and severe flooding events, tracking the explanatory elements of integrative planning effort can provide useful assessment of initiatives that foster improved community disaster resiliency. In this research, we address the effect of local hazard mitigation plan quality on mitigating disaster risk with an emphasis on the relationship between plan quality and community resilience. Using content analysis and principles of plan quality metrics, we evaluate local hazard mitigation plans to determine how well they support disaster risk reduction. Analytically, these metrics and relevant controls were incorporated into both a log-linear two-stage least squares model and a quantile regression model to explain flood loss at the county level for the US Mississippi River Basin. Findings suggest that better plan quality and high levels of community resilience result in reducing disaster losses.     

Hurricane Harvey and Greater Houston households: comparing pre-event preparedness with post-event health effects,event exposures,and recovery

Most disaster studies rely on convenience sampling and ‘after-only’ designs to assess impacts. This paper, focusing on Hurricane Harvey (2017) and leveraging a pre-/post-event sample of Greater Houston households (n=71) in the United States, establishes baselines for disaster preparedness and home structure flood hazard mitigation, explores household-level ramifications, and examines how preparedness and mitigation relate to health effects, event exposures, and recovery. Between 70 and 80 per cent of participants instituted preparedness measures. Mitigation actions varied: six per cent had interior drainage systems and 83 per cent had elevated indoor heating/cooling components. Sixty per cent reported home damage. One-half highlighted allergies and two-thirds indicated some level of post-traumatic stress (PTS). Three-quarters worried about family members/friends. The results of generalised linear models revealed that greater pre- event mitigation was associated with fewer physical health problems and adverse experiences, lower PTS, and faster recovery. The study design exposed the broad benefits of home structure flood hazard mitigation for households after Harvey.     

Social capital's role in recovery: evidence from communities affected by the 2010 Pakistan floods

Pakistan suffered large‐scale flooding in summer 2010 that caused damage amounting to approximately USD 43 billion, claimed the lives of at least 1,700 people, and negatively affected some 20 million others. Observers have debated the degree to which social capital plays a role in recovery after a catastrophe of this magnitude. Using new survey data on 450 residents impacted by the disaster, this study found that, controlling for various confounding factors, the social capital levels of victims serve as robust correlates of life recovery. Other important variables connected with recovery include education and income, family size, occupation, material damage suffered, stability of home, and trauma experience. The findings point to a number of relevant policy recommendations, most notably that during and following major shocks, disaster managers should work to keep the social networks of victims intact so that they can benefit from interaction with family, friends, and neighbours.     

深圳市洪涝灾害的数值模拟与分析

深圳市自建特区以来,沿河沿海低地迅速城市化,流域内大规模的开发活动加剧了水土流失,河道淤塞严重,行洪能力降低,新增市区防洪排涝设施不足,使深圳市洪涝灾害更趋频繁,经济损失急剧增长,为配合深圳市制定新的防洪(潮)规划,本研究开发了城市洪水演进一、二维不恒定流混合模型,分现状与规划措施实施后两种情况对各典型年暴雨、高潮的组合在深圳市可能造成的洪涝灾害进行了模拟和分析,其结果为深圳市合理评价防洪(潮)规划提供了依据。     

Flood risk and inequalities between ethnic groups in the floodplains of England and Wales

Previous research has shown that many vulnerable communities experience disproportional exposure to flood risk. This paper, though, is the first to look at broad ethnic/racial group differences in the United Kingdom. It contends that differences in culture and language, especially those of new immigrants, bestow vulnerabilities on such communities, resulting in a lack of knowledge that enables people to be aware, to be prepared, or to recover expediently after a flood emergency. Using UK 2011 Census data and Environment Agency flood maps, the paper demonstrates that it is the non‐white communities in Wales that confront the most disproportionate level of flood risk: 23 per cent as compared to 11.4 per cent of their white neighbours. In contrast, the difference in flood risk between white and non‐white ethnic/racial groups in regions of England is within a range of plus or minus two per cent, except for in Yorkshire and The Humber where white populations face a much greater risk of flooding.     

The Protection of China's Ancient Cities from Flood Damage

Over many centuries, the repeated and serious flooding of many of China's ancient cities has led to the development of various measures to mitigate the impact of floods. These have included structural measures, such as the construction of walls, dams and dykes, with tree planting for soil consolidation; installation of drainage systems and water storage capacity; the raising of settlement levels and the strengthening of building materials. Non-structural measures include warning systems and planning for emergency evacuation. Urban planning and architectural design have evolved to reduce flood damage, and government officials have been appointed with specific responsibilities for managing the flood control systems. In view of the serious consequences of modern neglect of these well-tried methods, this paper examines China's historical experience of flooding and demonstrates its continuing relevance for today. A brief historical survey is followed by a detailed discussion of various flood prevention measures. The paper is illustrated by city plans from ancient local chronicles.