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Over recent decades, remarkable progress in cultivating the concepts of flood risk management has taken place across countries as diverse as India, China, Australia, the UK and the USA. This change highlights a risk management paradigm as potentially more complex than a more traditional standardbased approach as it involves ‘whole systems’ and ‘wholelife’ thinking; yet this is also its main strength – paving the way for more integrated and informed decisionmaking. Strategic flood management (SFM) uses a portfolio of responses to manage flood risks and promote opportunities ecosystem services. It recognizes the interrelationships between the actions taken and the contribution flood management provides to integrated river basin and coastal zone planning. The paper results from an international collaborative effort for research and distils approaches to flood risk and water management in challenging largescale and complex environments. The paper provides an overview of the emerging good practice in SFM, including (i) an analysis of the flood events that have shaped changes in approach, (ii) the purpose and characteristics of modern SFM, (iii) the goals, objectives and outcomes sought and (iv) the challenges associated with implementation (together with some of the common pitfalls and misconceptions). Our conclusions are encapsulated in a set of ‘golden rules’ that underpin sound SFM decisionmaking.
This article was downloaded by: [14.162.168.57] On: 01 July 2014, At: 06:31 Publisher: Taylor & Francis Informa Ltd Registered in England and Wales Registered Number: 1072954 Registered office: Mortimer House, 37-41 Mortimer Street, London W1T 3JH, UK International Journal of River Basin Management Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/trbm20 Strategic flood management: ten ‘golden rules’ to guide a sound approach Paul Sayers ab , Gerry Galloway c , Edmund Penning-Rowsell de , Li Yuanyuan f , Shen Fuxin g , Chen Yiwei h , Wen Kang i , Tom Le Quesne j , Lei Wang k & Yuhui Guan l a Sayers and Partners, 24a High Street, Watlington OX49 5PY, UK b Senior Visiting Fellow, Environmental Change Institute, University of Oxford, Oxford, UK c Glenn L. Martin Institute Professor of Engineering, Department of Civil and Environmental Engineering, University of Maryland, College Park, MD, USA. Email: d Professor of Geography, Flood Hazard Research Centre, Middlesex University, London, UK e Distinguished Research Associate, Oxford University School of Geography and the Environment, Oxford, UK. Email: f Vice-President, Professor and Senior Engineer of the General Institute of Water Resources and Hydropower Planning and Design, Ministry of Water Resources, People's Republic of China. Email: g Professor-level Senior Engineer in the General Institute of Water Resources and Hydropower Planning and Design, Ministry of Water Resources, People's Republic of China. Email: h Engineer in the General Institute of Water Resources and Hydropower Planning and Design, Ministry of Water Resources, People's Republic of China. Email: i Senior Engineer and Former Director of the Flood Control Research Division at the Nanjing Hydraulic Research Institute, Ministry of Water Resources, People's Republic of China. Email: j Senior Policy Advisor, WWF-UK, Godalming, UK. Email: k Freshwater Programme, WWF-China, Beijing, People's Republic of China. Email: l Freshwater Programme, WWF-China, Beijing, People's Republic of China. Email: Published online: 03 Apr 2014. To cite this article: Paul Sayers, Gerry Galloway, Edmund Penning-Rowsell, Li Yuanyuan, Shen Fuxin, Chen Yiwei, Wen Kang, Tom Le Quesne, Lei Wang & Yuhui Guan (2014): Strategic flood management: ten ‘golden rules’ to guide a sound approach, International Journal of River Basin Management, DOI: 10.1080/15715124.2014.902378 To link to this article: http://dx.doi.org/10.1080/15715124.2014.902378 PLEASE SCROLL DOWN FOR ARTICLE Taylor & Francis makes every effort to ensure the accuracy of all the information (the “Content”) contained in the publications on our platform. However, Taylor & Francis, our agents, and our licensors make no representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the Content. 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Terms & Conditions of access and use can be found at http:// www.tandfonline.com/page/terms-and-conditions Downloaded by [14.162.168.57] at 06:31 01 July 2014 Research paper Strategic flood management: ten ‘golden rules’ to guide a sound approach PAUL SAYERS, Sayers and Partners, 24a High Street, Watlington OX49 5PY, UK; Senior Visiting Fellow, Environmental Change Institute, University of Oxford, Oxford, UK. Email: paul.sayers@sayersandpartners.co .uk (author for correspondence) GERRY GALLOWAY, Glenn L. Martin Institute Professor of Engineering, Department of Civil and Environmental Engineering, University of Maryland, College Park, MD, USA. Email: river57@comcast.net EDMUND PENNING-ROWSELL, Professor of Geography, Flood Hazard Research Centre, Middlesex University, London, UK; Distinguished Research Associate, Oxford University School of Geography and the Environment, Oxford, UK. Email: Edmund@penningrowsell.com LI YUANYUAN, Vice-President, Professor and Senior Engineer of the General Institute of Water Resources and Hydropower Planning and Design, Ministry of Water Resources, People’s Republic of China. Email: yyli@mwr.gov.cn SHEN FUXIN, Professor-level Senior Engineer in the General Institute of Water Resources and Hydropower Planning and Design, Ministry of Water Resources, People’s Republic of China. Email: Shenfuxin@giwp.org.cn CHEN YIWEI, Engineer in the General Institute of Water Resources and Hydropower Planning and Design, Ministry of Water Resources, People’s Republic of China. Email: chenyiwei.giwp@foxmail.com WEN KANG, Senior Engineer and Former Director of the Flood Control Research Division at the Nanjing Hydraulic Research Institute, Ministry of Water Resources, People’s Republic of China. Email: paulnsallie@aol.com TOM LE QUESNE, Senior Policy Advisor, WWF-UK, Godalming, UK. Email: tlequesne@wwf.org.uk LEI WANG, Freshwater Programme, WWF-China, Beijing, People’s Republic of China. Email: lwang@wwfchina.org YUHUI GUAN, Freshwater Programme, WWF-China, Beijing, People’s Republic of China. Email: yhguan@ wwfchina.org ABSTRACT Over recent decades, remarkable progress in cultivating the concepts of flood risk management has taken place across countries as diverse as India, China, Australia, the UK and the USA. This change highlights a risk management paradigm as potentially more complex than a more traditional standard-based approach as it involves ‘whole systems’ and ‘whole-life’ thinking; yet this is also its main strength – paving the way for more integrated and informed decision-making. Strategic flood management (SFM) uses a portfolio of responses to manage flood risks and promote opportunities eco- system services. It recognizes the interrelationships between the actions taken and the contribution flood management provides to integrated river basin and coastal zone planning. The paper results from an international collaborative effort for research and distils approaches to flood risk and water man- agement in challenging large-scale and complex environments. The paper provides an overview of the emerging good practice in SFM, including (i) an analysis of the flood events that have shaped changes in approach, (ii) the purpose and characteristics of modern SFM, (iii) the goals, objectives and outcomes sought and (iv) the challenges associated with implementation (together with some of the common pitfalls and misconceptions). Our con- clusions are encapsulated in a set of ‘golden rules’ that underpin sound SFM decision-making. Keywords: River basin management; strategic flood risk management; principles; international case study; risk; opportunity Received 9 January 2013. Accepted 5 March 2014. ISSN 1571-5124 print/ISSN 1814-2060 online http://dx.doi.org/10.1080/15715124.2014.902378 http://www.tandfonline.com 1 Intl. J. River Basin Management, 2014, 1–15 # 2014 International Association for Hydro-Environment Engineering and Research Downloaded by [14.162.168.57] at 06:31 01 July 2014 1 Introduction Flooding issues are always context specific. As a result, all flood- management plans differ in the specific combination of actions they prescribe. A common understanding of what constitutes ‘sound’ strategic flood management (SFM), however, is now starting to emerge. In particular, recent years have seen a general convergence on the concepts of risk (Sayers et al. 2002) and increasingly the definition of flood risk management (FRM) (Hall et al. 2003a, Samuels et al. 2010). These definitions are further developed here to reflect ‘SFM’ as follows: The process of data and information gathering, risk analysis and evaluation, appraisal of options, and making, implementing, and reviewing decisions to reduce, control, accept, or redistribute flood risks. It is a continuous process of analysis, adjustment and adaptation of policies and actions taken to reduce flood risk (including modifying the probability of flooding and its severity as well as the vulnerability and resilience of the receptors threa- tened). Strategic Flood Management (SFM) takes place as part of a wider approach of integrated basin or coastal planning and focuses on reducing flood risks and promoting environmental, societal and economic opportunities (both now and in the longer term). It recognizes that risks can never be removed entirely and that reducing risk is often at the expense of other societal goals. This definition is in contrast to a linear management model, based upon set standards and a more certain view of the future that is characteristic of traditional flood control decisions. It urges flood managers to recognize that future conditions may change (perhaps significantly) from those that exist today (Hall and Solomatine 2008, Milly et al. 2008) and seeks to embed resi- lience within the choices made (Sayers et al. 2012). It also under- lines the need for a continuous process of monitoring and intervention; reinvigorating the classical engineering control loop of data acquisition, decision-making, intervention and monitoring that now reappears in contemporary thinking about adaptive management (Willows and Connell 2003, McGahey and Sayers 2008, Sayers et al. 2012), as summarized in Figure 1. Building upon practice and theory, this paper presents a brief history of flood management and explores what sound flood management might be, and the barriers to its implementation. It concludes by suggesting a number of ‘golden rules’ that underlie a sound strategic approach. 2 Flood management: from where have we come? The earliest civilizations recognized the need to live alongside floods, locating critical infrastructure on the highest land (as seen through the medieval churches and cathedrals of England), providing flood warnings to those that may be flooded (common practice in ancient Egypt) and making flood- sensitive land-use planning choices (as often practised by the Romans). The requirement for protection and a belief in our ability to control floods started to increasingly dominate attempts to ‘deal with flooding’. Throughout the early and mid-decades of the twentieth century, engineers sought to control flood flows and defend areas from flooding. Typically, this was via the construc- tion of extensive levees systems and ring dykes, diversion chan- nels, dams and related structures. The perceived safety of the defended floodplains attracted development (for example, in New Orleans, London and Shanghai). Ecosystem became increasingly starved of the sediments and space upon which they rely (for example, in the Mississippi, Yangtze, Thames, Rhine and Danube), which in turn has affected the ecosystems services they provide. Despite the structural protection and the high price in the loss of ecosystem functions, flood losses continued to increase and the need for change became increasingly apparent. In response, through the latter part of the twentieth century, flood manage- ment was recognized not only as an engineering pursuit but also as a social endeavour (Baan and Klijn 2010). A new approach was needed, one that could not only identify the hazards and the consequences faced by society, but also assess the relative significance of the risks faced and the concepts of FRM (based upon a longer term, system-wide perspective) started to emerge (Sayers et al. 2002, Evans et al. 2004a, 2004b, Schanze 2006, Link and Galloway 2009, Samuels et al. 2010). In more recent years, the concepts of risk management have continued to evolve, in particular adopting an adaptive approach to managing flood risks, which works with natural pro- cesses, contributes positively to ecosystem services and forms part of an integrated basin or coastal management, is now emer- ging (WMO 2009, Sayers et al. 2013). This progression is reflected in Figure 2. Major flood events have often been pivotal in forcing and shaping these changes. For example, . 1917 and 1927 floods in the USA: At the dawn of the twentieth century, the universally preferred strategy within developed countries remained aimed at controlling floods locally. Increases in population and the agricultural potential of flood- plains continued to emphasize the need to ‘keep flood waters away’ from both valuable farm land and urban areas. Flood control was seen as a local or regional responsibility to be run by governments or quasi-governmental bodies at those levels. Flood control organizations within the same water- sheds only loosely coordinated with each other. Their focus was on protecting the area for which they were responsible no matter what the impact might be on other locations. The large floods in the USA in 1917 and 1927 were pivotal in chan- ging this view. The 1917 floods caused the US federal government to take a greater interest in the Mississippi River and the Sacramento River basins. It was recognized that local governance struc- tures were simply unable to deal with such major basin-wide floods and they sought federal fiscal support. In 1927, heavy storms across the Midwest created large floods in the lower Mississippi Valley that eventually breached a locally 2 Paul Sayers et al. Downloaded by [14.162.168.57] at 06:31 01 July 2014 Figure 1 SFM takes place as a continuous cycle of planning, acting, monitoring, reviewing and adapting. Source: Sayers et al.(2013). Figure 2 The evolution and development of flood management. Source: Sayers et al.(2013). Strategic flood management 3 Downloaded by [14.162.168.57] at 06:31 01 July 2014 controlled levee system and put hundreds of thousands of people out of their homes and off their lands for several months. It was labelled a national tragedy and brought about immediate attention from the national government. In 1928, by act of Congress, the US federal government assumed responsibility for construction and major maintenance of flood control structures in the lower Mississippi Valley. The ‘levees only’ policy was closely examined and deemed to be insufficient to deal with the challenge of major floods. A com- prehensive plan for flood control was to include strengthening of the levees, improvement of the channel to provide for natural maintenance, cut-offs of river bends that were seen to be delaying the flow of waters to the Gulf of Mexico, flood- ways to serve as pressure relief valves during major events and flood storage dams on the Mississippi River tributaries. Although limited in the context of a risk management approach, this was important progress in thinking that pro- moted the need for a basin-scale infrastructure and coordi- nation of action. . The 1947 and 1953 flood events in Europe: In March 1947, river floods occurred across much of Europe. The flooding was triggered by the rapid thaw of deep snow lying on a frozen catchment after one of the coldest and snowiest winters on record. The thaw was triggered by the arrival of a succession of south-westerly depressions, each bringing sig- nificant additional rainfall. Nearly all the main rivers in the south, midlands and the northeast of England were in flood with 30 out of 40 English counties impacted over a two- week period. Tens of thousands of people were temporarily displaced from their homes, and thousands of acres of crops lost. Shortly after the 1947 fluvial floods, Europe experienc ed devastating coastal floods in 1953 when a surge tide swept south through the North Sea overtopping and breaching many defences in England, the Netherlands and Belgium. The storm was at its peak during the night and with little or no warning. Flood waters breached defences and washed away homes as people slept. An estimated 2400 people lost their lives across Europe. On Canvey Island, at the mouth of the Thames Estuary, 58 people lost their lives as the defences breached. The net effect of these floods was to emphasize the fragility of structural defences; yet, as throughout history, the response was to increase the investment in levees, floodwalls, floodways and other structures. The event did, however, high- light the dramatic inadequacies in early warning systems and initiated the UK’s national Storm Tide Warning Service – a service that continues today. . Asia, 2004, Indian Ocean (Boxing Day) tsunami: An earth- quake in the Indian Ocean on 26 December 2004 triggered a series of devastating tsunamis along the coasts of most land- masses bordering the Indian Ocean, killing over 230,000 people in 14 countries, and inundating coastal communities with waves up to 30 m high. Indonesia was the hardest hit, together with Sri Lanka, India and Thailand. This event pro- vided two critical lessons for flood managers. The first was that given even the shortest of lead times, if you are able to warn people, they can react to reduce consequences if before the event they had gained an understanding of the risk and the appropriate actions to take. Prior to the Indian Tsunami, neither early warning systems nor awareness campaigns were in place. The second crucial lesson reflected the loss of critical infrastructure during the event. Many hospitals, trans- portation nodes and community centres were found be sited in some of the most exposed locations. As a result critical func- tions were lost at the time when they were most needed. Since 2004, considerable effort has been devoted to developing sophisticated early warning systems and mapping the prob- ability of flooding to inform spatial planning and emergency response decisions. The success of these measures is yet to be tested, but will, inevitably, be tested. A summary of these events, together with other pivotal floods over the past century, is given in Table 1. Until very recently, although always appreciated at a local scale and in academic terms, little attention was given to main- taining the beneficial relationship between floods and ecosystem services in actual flood-management planning. For example, in a near complete ignorance of the ecological value of wetlands, during the middle of the nineteenth century, the United States Congress passed legislation that supported the draining of wetland areas to provide room for agriculture and provided funding for flood control activities. The Congress saw little value in these periodically inundated areas. The lack of under- standing of the natural and beneficial functions of floodplains inherent in this legislation set the tone for the treatment of the floodplain environment that would continue in the USA over the next century and reflected practice across much of the Western world at that time (as testified by the infrastructure systems that remain, from the hidden rivers of London (Talling 2011) to the concrete lined trapezoidal channels characteristic of many urban storm channels in the USA and elsewhere). Settlement and development in the floodplain continue today with many of the world’s most dynamic cities located in river deltas and estuaries (Bangkok, Shanghai, New York, London, New Orleans and many others). This places more and more people and property in harm’s way and, as in the past, structural measures continue to dominate (see, for example, the development of major levees and sluices systems within the Taihu Basin, China (Xie et al. 2012) or the ‘Stormwater Management And Road Tunnel’ or ‘SMART Tunnel’ in Kuala Lumpur, Malaysia). In many developing countries, the reliance upon structural measures reflects not only the nature of the significant flood issues faced but also national policies that remain based on flood fighting and control rather than flood management. Elsewhere, continued development in the floodplain and reliance on single purpose structural measures appear to reflect a lack of imagination (in funding and design) rather than constraints within policy. Acceptance of the concepts of risk and SFM are therefore not enough and traditional flood defence or flood control paradigms 4 Paul Sayers et al. Downloaded by [14.162.168.57] at 06:31 01 July 2014 continue to persist, focused only upon reducing the probability of flooding through extensive structural defence systems (such as those in Rotterdam, Netherlands, New Orleans, USA, and on the Huai River, China). The challenge now is to turn th e now commonly accepted concepts of managing risks and promoting opportunities into common flood-management practice. Although there is no single roadmap to aid this transition, and few comprehensive examples, many elements of good practice are starting to emerge. For example, non-structural measures are being increasingly recognized as vital components of a broadly based approach to managing risk (Evans et al. 2004a, 2004b, US NRC 2012a) and various documents now reflect this direction of travel in modern FRM, including: . Investment choices that are based on a consideration of risk (US NRC 2000, Sayers et al. 2002). . Understanding the existing flood protection infrastructure; where it is, its condition and its performance on demand (Sayers et al. 2010). . Spatial planning that makes space for water (as embedded in the Room for the River policies in the Netherlands and Making Space for Water in England, Defra 2005) and controls the number and type of new developments in flood-prone areas (Burby and Dalton 1994). (a) Dual purpose buildings that provide a safe haven and a community facility such as a school or clinic (see, for example, the Bangladesh Flood Action Plan) and multi- purpose flood infrastructure (that contributes positively to the urban setting, providing amenity and ecosystem ser- vices in periods between floods, e.g. Maksimovic ´ et al. 2013). . Building codes and guides that promote flood resilience to speed recovery post flood (e.g. CIRIA 2010, USA). . Reliable and meaningful forecasts (of all forms of flooding) that help people prepare for flooding and, when necessary, evacuate to predetermined safe havens along well-rehearsed evacuation routes (Lumbroso et al. 2008). Table 1 The influence of past flood events in shaping policy and practice Flood event Impact on thinking, policy and/or practice 1917 Mississippi River and the Sacramento River basins, USA, and 1927 lower Mississippi, USA Promoted the need for basin-scale infrastructure and co-ordination 1931 and the following decades, across three major rivers: the Yellow, Yangtze and Huai, China Promoted the need for basin-scale infrastructure and co-ordination Major floods across the USA in 1936 (and to a lesser extent 1937 and 1951) Reinforced the need for national responsibility In March 1947, river floods occurred across much of Europe, shortly after Europe experienced devastating coastal floods in 1953 Issues of food security, the need for clear roles and responsibilities and the performance of warning systems 1991 and 1998 China A rethinking of flood issues: how to carry out disaster mitigation approaches more efficiently and effectively 1993 and 1997 Mississippi, USA The 1993 Mississippi River flood was the US flood of the century in economic terms. Following this event, new regulations were issued (1996) that established the need to include uncertainty in the assessment and justification for new flood control projects 1993, 1995, 1997 on the Rhine and 1998 in the UK Led to a demand for a new basin-wide and strategic approach to flood management using a combination of structural and non-structural approaches 2004, Asia Tsunami (Boxing Day) A recognition of the vulnerability of coastal communities and need for better warning, emergency planning and spatial planning to reduce risk 2005, New Orleans, USA A wider recognition that levees fail. A need to better understand levee performance and the wide acceptance of the need for a risk management approach and the communication of residual risks 2007 in Hull, UK Showed a need to consider all sources of flooding and spatial extent of events, as pluvial, fluvial and tidal sources combine 2010, Pakistan; 2011, Japan; 2011, Mississippi A need to re-evaluate the use of floodplains, limitations of structural systems and the need for improved resilience of critical infrastructure and prevent secondary and tertiary risks developing Source: Sayers et al.(2013). Strategic flood management 5 Downloaded by [14.162.168.57] at 06:31 01 July 2014 . Awareness among flood-management-related agencies, pro- fessional partners and the public to (i) enhance preparedness through the provision of readily accessible informat ion on flooding, including national flood mapping, available in the England and Wales for fluvial and coastal flooding since the mid-1990s (Environment Agency 2010) and increasingly internationally (including most recently the major national flood mapping initiative started in China, 2013) and (ii) post-flood recovery (US NRC 2012a). Increasingly, there is a move to map all sources of flooding with a coherent frame- work and some progress has been made. For example, the Environment Agency in England routinely provides infor- mation on pluvial flooding. . Secure and affordable insurance arrangements to compensate for flood losses (US NRC 2013). 3 The subtle dimensions of flood risk Before exploring what we believe to be sound SFM in more detail, it is first important to understand what is meant by risk in the context of flood management. Typically, as many authors have noted (US NRC 2000, Sayers et al. 2002), risk is considered as having two components the chance (or probability) of an event occurring and the impact (or consequence) associated with that event. A number of more subtle aspects underlie this simple under- standing of risk and bridge the gap from simply assessing the risk towards making risk-based decisions. The dimensions of risk that paint this richer picture are shown in Figure 3 and include the following four elements. . The probability of occurrence of inundation. This reflects both the probability of the occurrence of the initiating event (the source of the flood such as a single or sequence of rainfall or a marine storms, etc.) and the probability that flood waters reach a particular location in the floodplain (taking account of the floodplain topography as well as the performance of the intervening system of wetlands, channels, dams, levees, floodwalls and other structures: the so-called pathway of the flood water). Traditionally, the probability of inundation has been simply (and typically incorrectly) considered the same as the chance of the storm occurring. This is now changing. Modern analysis methods that incorporate a probabilistic description of the performance of intervening system (for example, accounting for the chance of levee failure) are starting to be embedded in practice (Hall et al. 2003b, Gouldby et al. 2010, Harris et al. 2010). . The consequences should flooding occur. This reflects both the vulnerability of the receptors and the chance that a given receptor will be exposed to the flood should it occur, where: (a) Exposure – quantifies the number of properties or people, area of habitats, etc. that may be exposed to a given flood event should it occur. Understanding exposure is not, however, as simple as it appears. For example, some recep- tors, such as residential properties, can be considered ‘static’, whereas receptors such as people, cars and much wildlife may be ‘dynamic’, and may or may not be present at the time of a flood. The time of day the flood occurs (rush hour; night time, etc.) and the actions taken to evacuate areas will both influence exposure, consider- ations that have for some time been addressed within a probabilistic manner within the context of dam safety (Hartford and Baecher 2004) but is only just starting to transition to flood-management planning. (b) Vulnerability – describes the potential for a given receptor to experience harm should it be flooded during a particular event. To further understand vulnerability, three support- ing aspects need to be considered: (i) Susceptibility – describes the propensity of a particular receptor to experience harm during a given flood Figure 3 The components of risk – to understand risk, the individual components of the risk must also be understood. 6 Paul Sayers et al. Downloaded by [14.162.168.57] at 06:31 01 July 2014 event. For example, a carpet may be damaged beyond repair, a particular flora or fauna may be lost or damaged and human death or injury. (ii) Value – the value system used to express the degree of harm to a receptor. For example, the damage may be monetized on the basis of traditional economics (Green 2003) or left in its native form (i.e. number of people killed) in which case relative weights may be provided nationally or, more progressively, deter- mined in the context of a particular choice. (iii) Resilience – describes the ability of the receptor that has been harmed to recover from the flood event and/or adapt to a change conditions that may have occurred in a timely and efficient manner. Understanding these multiple dimensions of risk is a prerequi- site of making informed management choices. Risks do not remain constant in time and all of their dimen- sions are subject to change – either through exogenous pressures (for example, climate change or socio-economic development largely beyond the influence of the flood manager) or in response to purposeful intervention (insurance regimes or indeed levees). Some changes act to increase risk (for example, development in the floodplain, loss of a communities flood memory, etc.) and others to either: . Reduce risk – Either through reducing the probability of flooding (e.g. through levee construction), the chance that they will be exposed to the flood when it occurs (e.g. through improved forecasting and warning) or by helping them to recover post event (e.g. providing institutional capacity to aid recovery). (a) Transfer risk – Among individuals and organizations. For example, insurance enables property owners to transfer part of their risk to others. Risk may be directly transferred to commercial (retail) insurance companies or to govern- ments (through compensation schemes such as in China), with the relative role of ‘free market’ and ‘state’ insurers reflecting the national political and social context. Retail insurers may then pass some of their aggregated risk to global reinsurances via reinsurance contacts or offered to investors via Catastrophe (CAT) Bonds. In some countries, to help maintain a viable insurance market premiums may be capped. In this case, the residual risk above the level covered by the capped premium may be transferred to CAT Pools that all insurers contribute to during periods of below average claims (the basis of Flood Re to be implemented in Eng land from 2015; Defra 2013) or under- written by the national government (such as a National Flood Insurance Program operated by FEMA in the USA; US NRC 2013). Further general discussion of these issues can be found in the following papers: Raschky (2007), Kunreuther and Heal (2012), and Ermo- lieva and Ermoliev (2013). 4 What then is the purpose of flood management? The overarching motivation for flood management is to support the broader aims of sustainable development (WCED 1987,UN 1992, US NRC 2012b). In particular, SFM can play a pivotal position in promoting desired societal, environmental and econ- omic outcomes. As such, and in contrast to the often narrowly defined single objective nature of flood control paradigm, SFM places an emphasis not only on reducing risk (to people, econ- omics and the environment) but also on seeking opportunities to working with natural processes and promoting multiple benefits across a range of criteria (ecological, societal and econ- omic). The trade-off between the resources required and benefits accrued lies at the heart of investing limited resources effectively and efficiently (Figure 4). Figure 4 The primary goals of SFM. Strategic flood management 7 Downloaded by [14.162.168.57] at 06:31 01 July 2014 Supporting sustainability through a strategic approach to flood management is therefore much more than simply maintain- ing the long-term integrity of flood control structures: a common misconception in many parts of the world. It also includes pro- moting the long-term health of the associated ecosystems, societies and economies. The manner in which these higher level goals are translated into poli cy objectives shapes the nature of the FRM that is delivered. In particular, the way in which the following three issues are addressed in policy terms and translated into SFM plans is crucial: (1) Efficiency and fairness – Flooding, and actions taken to manage floods, are not fair per se: the inherent natural spatial inequality in the frequency and extent of flooding, plus the legacy of past interventions and the coverage of new ones being the cause. Every intervention to manage flood risk inevitably tends to prioritize one group or location over another, creating further inequality and ‘unfairness’. In general, it is accepted that decision-makers must seek to maximize the utility of an investment while ensuring that it is distributed through a just process that also protects the most vulnerable members of society. Achieving this in reality raises a number of practical problems. Providing pro- tection to one community but not another is inherently unfair; providing a higher level of protection to one com- pared to another is also unfair. Providing a common level of protection to all would be, however, impractical, and even if achievable would be grossly inefficient. The desire to manage flood risk more fairly is best achieved through the use of nationally consistent non-structural strategies that are available to all (for example, better forecasting and warning arrangements; improved building codes and enhanced emergency response schemes). Such an approach offers a greater contribution to fairness and vulnerability- based social justice principles than engineered solutions that, by their nature, deliver benefits to some but not others (Table 2). (2) Resilience and adaptive management – Both developed and developing countries are seeking to promote communities that are resilient and capable of adapting to unknown future changes. Both are struggling to turn good theory into practical action. As yet no blue print is available as to what constitutes a resilient community, resilient design or adaptive management. A common understanding is, however, starting to emerge, recognizing resilience as an emergent property of an individual, community or organiz- ation that is promoted through (in part): . Promoting resilient infrastructure – Strategies based upon a wide portfolio of structural and non-struc - tural responses typically offer a degree of redun- dancy that promotes greater resilience than relying upon a single measure. Strategies, however, consist- ing of individual response and structural measures will continue to remain a legitimate component in all but the lowest of risk areas (Evans et al. 2004a, 2004b). ‘Resilient design’ fosters an innova- tive approach to the design, construction and oper- ation of these (US National Institute of Building Sciences, Bosher et al. 2007, NIBS n.d.). This can help ensure that an acceptable level of performance is maintained when exposed to events more severe than anticipated (i.e. levees should not breach when a notional design level has been exceeded nor should their performance decay catastrophically without warning). Table 2 Socio-cultural justice – influence on FRM decisions Justice principle (type) Rule/criteria Meaning for FRM Potential implications for FRM Equality (procedural) All citizens to be treated equally Every citizen should have the equal opportunity to have their flood risk managed A greater focus on vulnerability reduction and state- sponsored self-help adaptations that can be provided for all – avoiding the inherent unfairness in providing structural solutions that benefit the few Maximin rule (distributive) Options chosen to be those that favour the worst-off best Resources should be targeted to the most vulnerable Need to identify, and target assistance at the most vulnerable members of society, even when greater economy returns can be found elsewhere Maximize utility (distributive) Options chosen to those that secure the greatest risk reduction per unit of resource input Assistance provided to those members of society to which the benefits offer the greatest gain to society Need to identify a set of measures that deliver the greatest risk reduction for minimum resource – likely to be associated with a broad range of measures. The greatest risk reduction, for the most vulnerable, most likely to be provided in the form of non-structural responses, for example, state- assisted self-help homeowner adaptations and improved preparedness, etc. with more capitally intensive structural solutions provided to areas of high economic activity 8 Paul Sayers et al. Downloaded by [14.162.168.57] at 06:31 01 July 2014 [...]... manage risk (where the advantages of several FRM measures are greater than the sum of the advantages of each measure taken separately) (Table 4) Operates as a continuous process that monitors, reviews and adapts to the future as it becomes known This approach is distinct from the ‘implement and maintain’ philosophy in the traditional flood defence approach These four characteristics of an SFM plan are... urban drainage systems) Land management: forestry/floodplain woodland, ponds and wetlands, field scrape/infiltration trench, soil management, riparian buffer strips, etc Influencing the pathway of flood waters: Through, for example, morphological, debris and vegetation management, wetland and washland creation as well as permanent and temporary structural defences, pumps and barriers Reduce the potential... flood risk management Proceedings of the International Association of Hydraulic Research, IAHR, European Congress, May 2010, Edinburgh Available from: http://web.sbe.hw.ac.uk/ staffprofiles/bdgsa/IAHR_2010_European_Congress/Papers% 20by%20session%20final /Flood% 2 0Management% 20III/FMa IIIa.pdf [Accessed 24 March 2013] Sayers, P., Hall, J., and Meadowcroft, I., 2002 Towards riskbased flood hazard management. .. Galloway, G.E., and Hall, J.W., 2012 Robust decision making under uncertainty – towards adaptive and resilient flood risk management infrastructure In: P.B Sayers, ed Flood risk: planning, design and management of flood defence infrastructure London: Thomas Telford, 281–302 Sayers, P., et al., 2013 Flood risk management: a strategic approach [online] Asian Development Bank, Manila; China General Institute... plausible all future scenarios, (iii) observes change through targeted monitoring and continues to reassess scenarios of the futures and (iv) appropriately modifies policies, strategies and structure plans Maintaining future flexibility (to either raise a defence or make a significant change in approach, such as abandon a town) can cost additional resources today (e.g to strengthen foundations in preparation... and the USA The contributions of these organizations are acknowledged The project was supported by the HSBC Climate Partnership, via a grant to WWF-UK and designed to research and disseminate modern approaches to water management in challenging environments, and provide new insights into strategic planning and risk management of water resources This paper focuses on strategic FRM and is one in a series... [14.162.168.57] at 06:31 01 July 2014 Strategic flood management US National Research Council (NRC), 2000 Risk analysis and uncertainty in flood damage reduction studies [online] Washington, DC: The National Academies Press Available from: http://www.nap.edu/catalog/9971.html [Accessed 18 November 2013] US National Research Council (NRC), 201 2a Disaster resilience: a national imperative Washington, DC: The National... National Academies Press US National Research Council (NRC), 2012b Dam and levee safety and community resilience: a vision for future practice Washington, DC: The National Academies Press US National Research Council (NRC), 2013 Levees and the National Flood Insurance program Washington, DC: National Academy Press Walsh, C.L., et al., 2013 Experiences of integrated assessment of climate impacts, adaptation... the chance of damage through the provision of ‘strong’ structures, and adaptive management is much more than simply ‘wait and see’ Both are purposeful approaches to strategy development and design that are inherently risk based and importantly, seek to actively manage uncertainty Accepting the future as unknown has a number of profound implications that are in contrast to the linear model of strategy... sector, is in harmony with associated activities in other levels of government and sectors As such sound floodmanagement planning requires a paradigm of governance that is collaborative and blurs the distinction between the disciplines of spatial, coastal zone, river basin and water resources planning as well as flood defence engineering and environmental management This is not easy and achieving meaningful . diverse as India, China, Australia, the UK and the USA. This change highlights a risk management paradigm as potentially more complex than a more traditional standard-based approach as it involves ‘whole. basin and coastal zone planning. The paper results from an international collaborative effort for research and distils approaches to flood risk and water man- agement in challenging large-scale. that exist, within and across sectors; an understanding that is rapidly developing (Hall et al. 2013) but will demand coordinated action to main- stream into practice. . Adopting adaptive management