New policies to deal with climate change and other drivers impacting on resilience to flooding in urban areas: the CORFU approach

In the context of urban flood management, resilience is equal to resisting, recovering, reflecting and responding. The variety of causes of flooding and their consequences underpin the need for increased and internationally coordinated efforts to enhance technologies and policies for dealing with floods. This paper addresses this issue and presents some novel research ideas related to resilience to flooding in urban areas, which are under development within the EU FP7 project ‘Collaborative research on flood resilience in urban areas’ (CORFU). The approach adopted in this project aims to quantify the cost-effectiveness of resilience measures and integrative and adaptable flood management plans for different scenarios of relevant drivers: urban development, socio-economic trends and climate changes. It is believed that the way in which the different models are being put together, combined with the variability of conditions in case study areas in Asia and in Europe, will ultimately enable more scientifically sound policies for the management of the consequences of urban flooding.     

Flash flood forecasting, warning and risk management: the HYDRATE project

The management of flash flood hazards and risks is a critical component of public safety and quality of life. Flash-floods develop at space and time scales that conventional observation systems are not able to monitor for rainfall and river discharge. Consequently, the atmospheric and hydrological generating mechanisms of flash-floods are poorly understood, leading to highly uncertain forecasts of these events. The objective of the HYDRATE project has been to improve the scientific basis of flash flood forecasting by advancing and harmonising a European-wide innovative flash flood observation strategy and developing a coherent set of technologies and tools for effective early warning systems. To this end, the project included actions on the organization of the existing flash flood data patrimony across Europe. The final aim of HYDRATE was to enhance the capability of flash flood forecasting in ungauged basins by exploiting the extended availability of flash flood data and the improved process understanding. This paper provides a review of the work conducted in HYDRATE with a special emphasis on how this body of research can contribute to guide the policy-life cycle concerning flash flood risk management.     

Flood inundation uncertainty: The case of a 0.5% annual probability flood event

Aging coastal defences around the UK are challenging managers to redesign schemes to be resilient to extreme events and climate change, be cost-effective, and have minimal or beneficial environmental impact. To enable effective design, reduced uncertainty in the assessment of flood risk due to natural variability within the coastal forcing is required to focus on conditions that pose highest threat. The typical UK standard of protection for coastal defences is to withstand a 0.5% annual probability event, historically also known as a 1 in 200 year return period event. However, joint wave-water level probability curves provide a range of conditions that meet this criterion. We examine the Dungeness and Romney Marsh coastal zone, a region of high value in terms of habitat and energy assets, to quantify the uncertainty in flood depth and extent generated by a 0.5% probability event, and to explore which combinations of wave and water levels generate the greatest threat.     

Bringing flood resilience into practice: the FREEMAN project

The recent shift in flood risk management concedes that floods cannot be prevented but the impacts on and vulnerability of the risk prone communities can be reduced. Beyond mere structural defence, an integrated risk management approach deploys a diversified set of measures that moderate the economic and social drivers of risk and improve risk governance. In this context, the concept of resilience gains on importance despite the many challenges that obstruct its implementation in management practice. This paper contributes to tackling these challenges and elaborates on opportunities and bottlenecks to bring resilience into practice based on a review of the flood risk management in three case studies in Europe: Flanders (Belgium), Niedersachsen (Germany) and Calabria (Italy). The paper summarizes insights gained on three components of resilience being – institutional interplay, flood management tools and risk communication. The work that has lead to this paper is done under the FREEMAN project (flood resilience enhancement and management), funded under the 2nd CRUE ERA-Net Funding Initiative.     

Improving flood risk analysis for effectively supporting the implementation of flood risk management plans: The case study of “Serio” Valley

The EU Flood Directive 2007/60 requires the assessment and delineation of flood risk maps. The latter should provide the required knowledge for the development of flood risk management plans (FRMPs), that should deal with all features of risk management: e.g. preparation, protection and prevention, comprising also the phase of the flood forecasting and warning systems, in addition to the emergency management. The risk maps, delineated through the expert-drive qualitative (EDQ) approach currently adopted in several European countries, such as Italy, fail to represent the information base that needed by stakeholders for selecting the suitable objectives and designing the appropriate mitigation actions for flood risk management. In the EDQ approach, the flood hazard and the potential damage degree maps are combined by means of a matrix to obtain a qualitative flood risk map. However, the performance of the risk matrix is not usually rigorous validated and, therefore, presents limits, such as subjective and not careful explained interpretation of rating and poor resolution, (due to range compression), that can produce errors in comparative ranking of risk areas. In this context, this paper proposes the FloodRisk approach that aims to improve the efficacy of flood risk map overcoming the limits of EDQ approach in supplying the knowledge base that allow to analyze costs and benefits of potential mitigation measures. However, the proposed approach is also able to involve the citizens in the flood management process, enhancing their awareness. An application of FloodRisk procedure is showed on a pilot case in “Serio” Valley, (North Italy), and its strengths and limits, in terms of additional efforts required in its application compared with EDQ procedure, have been discussed focusing on the efficacy of the outcomes provided for the fulfillment of FRMPs. The results have demonstrated the ability of FloodRisk, respect to EDQ approach, to distinguish successfully different levels of vulnerability of exposure elements, thanks to the use of asset value and depth-damage curves, that allows a suitably evaluation of the effectiveness of risk mitigation strategies. In this light, a successfully application of a cost-benefit analysis of FloodRisk approach on a portfolio of alternative mitigation actions, (i.e. structural and non-structural measurements), has been demonstrated on the proposed study case. However, FloodRisk requires additional information, e.g. water depths assessment and assets values, and it needs a proper analysis and communication of the uncertainty in its results. Although they still exist limitations that impede, at present, the FloodRisk application without an adequate understanding and a critical consideration of the hazard, exposure and vulnerability characteristics of the study area, considerations are supplied on how the utilization of this approach can be maximized in the light of the next flood risk maps revision due by December 2019.     

Perceptions of climate change risks and resilient island planning in the Maldives

This article explores the drivers, benefits, and challenges facing climate change adaptation in the Maldives. It specifically investigates the ??Integrating Climate Change Risks into Resilient Island Planning in the Maldives?? Program, or ICCR, a four-year $9.3 million adaptation project being funded by the Least Developed Countries Fund, Maldivian Government and the United Nations Development Program, and nationally executed by the Ministry of Housing, Transport and Environment of the Maldivian Government. The article asks: what is the perception of coastal adaptation in the Maldives, and what are the potential contributions from the ICCR project? To answer this question, the article summarizes eight primary sectors vulnerable to climate change in the Maldives: human settlements, critical infrastructure, tourism, fisheries, health systems, water, food security, and coral reef biodiversity. It then describes the genesis and background behind the ICCR, which addresses many of these vulnerabilities by demonstrating coastal protection measures. Benefits to the ICCR include improving physical resilience by deploying ??soft?? infrastructure, institutional resilience by training policymakers and enhancing good governance, and community resilience by strengthening community assets and awareness. Challenges include ensuring that adaptation efforts are enough to truly respond to climate vulnerability, lack of coordination, and short-term thinking among business and community leaders.     

A framework for evaluating flood risk governance

Calls to strengthen flood risk governance are echoed across Europe amidst a growing consensus that floods will increase in the future. Accompanying the pursuit of societal resilience, other normative agendas relating legitimacy (e.g. accountability and public participation), and resource efficiency, have become attached to discussions concerning flood risk governance. Whilst these represent goals against which ‘success’ is socially and politically judged, lacking from the literature is a coherent framework to operationalise these concepts and evaluate the degree to which these are achieved. Drawing from cross-disciplinary and cross-country research conducted within the EU project STAR-FLOOD, this paper presents a framework for evaluating the extent to which flood risk governance arrangements support societal resilience, and demonstrate efficiency and legitimacy. Through empirical research in England, this paper critically reflects on the value of this approach in terms of identifying entry points to strengthen governance in the pursuit of these goals.     

Advancing urban ecosystem governance in Ljubljana

Extensive green areas generate a recognizable green identity of Ljubljana. Due to the challenges of climate change and urbanization the city's spatial policy highlights revitalization of degraded urban areas, preserving the quality and scope of the existing green network and the protection of multifunctional natural areas surrounding the city. Article describes the project of Rakova Jelša Park as a good example of these policies. With an NGO initiative a former degraded area with illegal dumping and non-indigenous vegetation was transformed into recreational park with increased biocultural diversity. Important lesson of the project is that opening up space for public use not only prevents degradation, but also improves the quality of urban ecosystems. One of the challenges for the city's future sustainable ecosystem development will be a more active cooperation with its citizens in the green infrastructure policy and later also a partial transfer of responsibility for green areas to them.     

我国环境保护投资与经济发展及COD排放关联研究

近些年来,我国环保投资一直保持较快增长,但变化波动较大,缺乏长期、稳定的资金来源渠道,尚未形成与经济发展之间稳定的联动机制.从总量上看,尽管环保投资与固定资产投资存在长期均衡关系,但是从增量上看,环保投资并非固定资产投资优先领域.环保投资对COD排放量存在一定影响,但由于投资结构的不合理,环境效益难以有效发挥.主要体现在:一定比重的城市环境基础设施投资与环境治理关系不密切;工业污染源治理投资规模一直偏低,难以发挥规模效应;建设项目“三同时”环保投资环境效益的实现存在较明显的时滞性.本研究基于以上分析,提出构建环保投资增长与经济发展的内生增长机制、优化环保投资结构、规划编制与实施应统筹考虑环境效益滞后因素等政策建议.     

The conception of public interest in Dutch flood risk management: Untouchable or transforming?

The governance of flood risks varies considerably in different parts of the world. Obviously this is due to the nature and characteristics of flood risks, but in part governance approaches vary because of political differences in the nature of governance itself. What is ‘appropriate’ in this respect depends partly on the prevailing conceptions of the public interest in a country. By applying Alexander’s (2002) categorization of public interest to flood risk management practices in The Netherlands, we show that the strongly unitary conception of the public interest (a historic ‘flood risk safety for all’), is intertwined with a state-based, sector-based, hydro-technical governance and expertise system. Although this conception is very strong it is no longer self-evident. Because of changing conceptions of governance in general and because of the felt necessity to adapt to climate change, Dutch flood risk management is gradually changing. Increasingly, the Dutch government has to deal with more dialogical and utilitarian approaches to public interest in the governance of flood risks. The Dutch approach is rooted in community-based interests in flood protection and was centralized and rationalized during the 19th and 20th century. The current flood risk standards are based upon a coarse utilitarian benefit-cost analysis, but evolved into mostly a unitary idea of national safety materialized in law by statutory flood risk standards. The findings show that this unitary concept and status of the public interest of flood risk safety has not diminished; it must, however, increasingly take into account the importance of both processes of decision making (dialogues, deliberations) and neighboring public interests. We conclude that the Dutch conception of the public interest on flood safety is still strong but nevertheless gradually changing, not the least because of a general availability of the information and technology to calculate and differentiate risks.     

A flood risk decision making approach for Mediterranean tree crops using GIS; climate change effects and flood-tolerant species

The aim of this study is to estimate flood risk in the Mediterranean island of Crete in Greece, using Geographic Information Systems (GIS). The island of Crete, covering an area of 8265 km², is one of the most intensively Mediterranean agricultural areas dominated by fruit tree crops. In this study, the factors that are directly related to the creation of a flood are combined in a GIS environment in order to identify the most prone flooding areas. These factors are: (a) the Flow accumulation (F), (b) the Rainfall intensity (R), (c) the Elevation (E), (d) the Geology (G), (e) the Land use (L), and (f) the Slope (S). The initials of these factors gave the name to the proposed method: “FREGLS”. The above factors are presented in the form of grid maps and are used in order to determine the final flood risk map. Subsequently, the flood prone fruit tree areas of Crete can be estimated by applying a methodology based on weighting coefficients. The reliability of the final flood risk map is verified using historical flooded data. Additionally, the impact of global climate change scenarios A2 and B1, on flood risk in Crete is examined. Based on the above, this study highlights the flood prone fruit tree areas in the island of Crete under current and future climate conditions. Also, flood-tolerant fruit trees which appear to be economically important for Greece are recommended, especially for the high flood risk areas of the island. The proposed methodology can be applied as a decision making tool for flood risk mitigation to any river basin where tree crops are cultivated.     

Need for adaptation strategy against global sea level rise: an example from Saudi coast of Arabian gulf

This paper reports sea level rise (SLR) scenarios causing land loss, environmental degradation and destruction of infrastructure in the Saudi coast of the Arabian Gulf. Human development structures such as, sea ports, desalination plants, industrial establishments, commercial buildings, fish farms etc. will be impacted, leading to great economic losses. A systematic analysis on the current environmental setting of east coast of Kingdom of Saudi Arabia (KSA) versus the existing infrastructure assets indicates that a 1?m sea level rise in Arabian Gulf affects approximately 650?km² land area, along the Saudi coastline of ~1,800?km in 1:50,000 scale. Three simulation scenarios were created with respect to 1?m, 2?m and 3?m rises from the present mean sea level and its impacts were assessed. Maps depicting major infrastructure assets, ecologically sensitive elements, historical locations, anthropogenic zones, and Environmental Sensitivity Indices (ESI) were used for overlaying the sea level change map, in a Geographic Information System (GIS) platform. In general, the Jubail Marine Park area will have serious impact due to SLR. The inundation of low?Clying lands will affect the mangroves species of Dawhat Ad Dafi, coral reefs, coastal salt marshes, groundwater aquifers, and fish stocks. The risk of inundation on the Abu Ali Island, given their status as marine sanctuary of international importance, is particularly high. As an adaptation strategy, it is proposed that the KSA should implement Integrated Coastal Zone Management Plan (ICZMP) for the Arabian Gulf coast without further delay for the protection of its vulnerable resources and for sustainable development.     

Coastal flood protection: What perspective in a changing climate? The THESEUS approach

Coastal areas are vital economic hubs in terms of settlement, industry, agriculture, trade and tourism to mention some key sectors. There are already many coastal problems including erosion, flood risk and long-term habitat deterioration. As economies continue to develop the asset base at risk will grow, while accelerating climate change will increase the likelihood of damaging extreme events, as well as accelerate habitat decline. Existing coastal management and defence approaches are not well tuned to these challenges as they assume a static situation.THESEUS project is developing a systematic approach to delivering both a low-risk coast for human use and healthy habitats for evolving coastal zones subject to multiple change factors. The project examines innovative mitigation and adaptation technologies and integrate the best of these technical measures in a strategic policy context through overarching guidelines. THESEUS activities are carried out within a multidisciplinary framework using 8 study sites across Europe, with specific attention to the most vulnerable coastal environments such as deltas, estuaries and wetlands, where many large cities and industrial areas are located.This paper describes THESEUS approach, and specifically: the Source-Pathway-Receptor-Consquence model for coastal risk assessment; the engineering, social, economic and ecological mitigation measures under analysis; the participatory approach with end users and coastal authorities for the selection and identification of the appropriate defence strategy to be planned in sudy sites.     

Carbon footprint analysis for increasing water supply and sanitation in South Africa: a case study

This study investigates the environmental burdens due to the provision of potable water and sanitation in the eThekwini Municipality (Durban), South Africa. This was achieved by employing LCA studies for the individual parts of the urban water system (impoundment, water treatment, distribution, collection, sewage treatment and water recycling). Based on the results of the individual LCAs a base case was constructed.For the provision of potable water and sanitation to new customers, which have not been previously served, two different scenarios (200 000 new customers in an urban environment with waterborne sewage and in a peri-urban environment with on-site sanitation) and three different options (maximising use of existing assets, recycling water and building new infrastructure) were considered and analysed. With regard to the impact scores calculated for both scenarios (urban and peri-urban), the recycling of water is followed by maximising the use of existing assets as the most environmentally friendly options. The construction of new infrastructure carries a higher environmental burden and the use of bottled water for drinking (an additional scenario) carries the highest environmental burden.     

Historical assessment of Chinese and Japanese flood management policies and implications for managing future floods

Floods are among the world's most devastating natural disasters, causing immense damage and accounting for a large number of deaths world-wide. Good flood management policies play an extremely important role in preventing floods. It is well known that China has more than 5000 years of experience in flood management policy beginning with the reign of DaYu and Gun. Although culturally related, Japanese flood management developed differently from that of China. Under rapid development of civil engineering technology, flood management was achieved primarily through the construction of dams, levees and other structures. These structures were never adequate to stop all floods, and recent climate change driven extreme events are ever more frequently overwhelming such infrastructure. It is important to take a historical perspective of Japanese and Chinese flood management in order to better manage increasingly frequent extreme events and climate change. We present insights taken from an historical overview of Japanese and Chinese flood management policies in order to guide future flood risk management policy.     

Prescriptive conflict prevention analysis: An application to the 2021 update of the Austrian flood risk management plan

Flood events have become more frequent in Europe, and the adaptation to the increasing flood risks is needed. The Flood Directive set up a series of measures to increase European resilience, establishing Flood Risk Management Plans (FRMPs) at the level of the river basin district as one relevant action. In order to efficiently fulfil this objective, the involvement of stakeholders as well as the analysis of their roles, responsibilities, and demands has been considered to be crucial to develop FRMPs. As a result, the hypothesis tested in this paper is that a consensus solution for the 2021 update Austrian Flood Risk Management Plan is feasible. To demonstrate this, both in-depth interviews and questionnaires to key Austrian stakeholders are implemented. The information collected in both participatory techniques are then used to run a conflict prevention analysis. The results show that (a) improving the coordination among regions and including better land-use planning approaches are preferable to a hypothetical business as usual scenario; and (b) a consensus solution for the 2021 update Austrian FRMP might be achievable on the basis of both a deep discussion on the state-of-the art and green infrastructure development.     

Combining hazard,exposure and social vulnerability to provide lessons for flood risk management

Flood risk assessments provide inputs for the evaluation of flood risk management (FRM) strategies. Traditionally, such risk assessments provide estimates of loss of life and economic damage. However, the effect of policy measures aimed at reducing risk also depends on the capacity of households to adapt and respond to floods, which in turn largely depends on their social vulnerability. This study shows how a joint assessment of hazard, exposure and social vulnerability provides valuable information for the evaluation of FRM strategies. The adopted methodology uses data on hazard and exposure combined with a social vulnerability index. The relevance of this state-of-the-art approach taken is exemplified in a case-study of Rotterdam, the Netherlands. The results show that not only a substantial share of the population can be defined as socially vulnerable, but also that the population is very heterogeneous, which is often ignored in traditional flood risk management studies. It is concluded that FRM measures, such as individual mitigation, evacuation or flood insurance coverage should not be applied homogenously across large areas, but instead should be tailored to local characteristics based on the socioeconomic characteristics of individual households and neighborhoods.     

Using participatory geographic approaches for urban flood risk in Santiago de Chile: Insights from a governance analysis

Studies based on information acquired by participative geographic approaches have sought to cope with emergency situations and disasters such as floods. However, the impact of these approaches to flood risk governance systems in order to understand these types of events as a complete risk cycle is still not clear. This paper focuses on analysing the governance possibilities of using participative geographic information like volunteered and public participatory geographic information for flood risk reduction in the case of Santiago de Chile, a city which regularly experiences urban floods during rainy seasons. Based on in-depth interviews and document analysis, our study indicates that a relevant part of the current information used for flood risk reduction efforts is provided to local and regional authorities by the affected population. Though, local actors are not recognized by central agencies as valid agents for the production of official information. Moreover, there are neither instances of communication or deliberation with the community, which reduces the capacity of local actors to discuss possible solutions. Participative geographic instruments are seen as potential mechanisms to strengthen work relations among local actors and authorities, by enhancing new logics for producing and sharing information. The impacts for the current risk governance system though can be diverse depending on the participants' level of commitment of participants and the political relations between actors and agencies. Considered as merely data acquisition and analysis mechanisms, participative instruments reproduce the existing hierarchical top-down structures. Furthermore, local-based approaches can enhance local work, support local diagnostics and increase the decision capacity of citizens.     

社会—生态系统适应性治理视角下绿地空间恢复力的演化——广州旧城区更新案例

旧城区绿地作为关键的社会—生态系统载体,是城市高质量发展与转型治理亟需关注的问题。构建广州旧城区绿地服务基本单元,引入适应性循环理论的潜力—连通度—恢复力三维框架,构建表征生态、社会与经济服务的绿地景观指标体系,综合评估2000—2018年广州旧城区绿地的空间恢复力水平及适应性转化特征。研究结果显示：旧城区绿地的恢复力演化具有明显的核心区与外围区的时空分异,在拆除重建阶段呈现快速开发—快速释放—重组的转化,在微更新阶段主要呈现开发—保护的提升,并具有提升型、稳定型和更替型的社会—生态系统服务适应性。由此说明,城市更新具有调节社会—生态系统服务治理的效果。其中,绿地形状指数、5 min可达绿地率以及土地利用混合度对核心区绿地恢复力具有显著的促进作用,为外围区治理提供参考。同时,进一步探讨了更新政策与城市绿地空间恢复力演化的关系,为促进旧城区绿地空间更新治理提供社会—生态系统适应性的理论与实证案例研究。     

A comparative appraisal of the use of rainwater harvesting in single and multi-family buildings of the Metropolitan Area of Barcelona (Spain): social experience,drinking water savings and economic costs

Many urban areas suffer water scarcity but paradoxically, a local source of water such as rainwater is mostly treated as a risk rather than as a valuable resource. Scepticism regarding the use of rainwater harvesting technologies still prevails today, particularly in low precipitation areas. However, some regions such as the Metropolitan Area of Barcelona (MAB) have started to promote the use of rainwater through specific regulations and incentives. This paper aims to examine the use of rainwater harvesting in the two main types of buildings prevalent in the MAB by analysing users’ practices and perceptions, drinking water savings and economic costs. Despite low precipitation inputs and a high variability of precipitation, daily balances show that toilet flushing demand of a single family house can be practically met with a relatively small tank. Rooftop rainwater can also meet more than 60% of the landscape irrigation demand in both single and multi-family buildings. The main drawback is the long pay-back period that rainwater harvesting systems present today. Nevertheless, it is remarkable that in multi-family buildings residents usually take no notice of the costs associated with the system. In contrast, benefits for the whole society are usually much more appreciated. Users’ reactions and their level of satisfaction towards rainwater harvesting systems suggest that both regulations and subsidies are good strategies to advocate and expand rainwater harvesting technologies in residential areas. However, a multidirectional learning environment needs to be promoted to ensure a proper use of rainwater harvesting systems and risk minimisation.