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Über dieses Buch

This book examines changes and transitions in the way water is managed in urban environments. This book originated from a joint French-Australian initiative on water and land management held in Montpellier, France. The book delivers practical insights into urban water management. It links scientific insights of researchers with the practical experiences of urban water practitioners to understand and respond to key trends in how urban water is supplied, treated and consumed. The 51 contributors to the volume provide a range of insights, case studies, summaries and analyses of urban water and from a global perspective. The first section on water supply and sanitation includes case studies from Zimbabwe, France and South Africa, among others. Water demand and water economics are addressed in the second section of the book, with chapters on long-term water demand forecasting, the social determinants of water consumption in Australian cities, a study of water quality and consumption in France, governance and regulation of the urban water sector and more. The third section explores water governance and integrated management, with chapters on water management in Quebec, in the Rotterdam-Rijnmond urban area, in Singapore and in Australia. The final section offers perspectives on challenges and future uncertainties for urban water systems in transition. Collectively, the diverse insights provide an important step forward in response to the challenges of sustainably delivering water safely, efficiently and equitably.



Chapter 1. Understanding and Managing Urban Water in Transition

Understanding and managing water in the urban context is of vital global importance. Over half the world’s population now lives in urban environments (United Nations 2013) and the percentage is set to increase over coming decades. Quality urban living, like life anywhere, requires adequate quantities and qualities of water to support a range of social well-being, economic development, and environmental health. Managing water in cities, along with their linked energy, food, materials, environmental systems, and socio-economic systems is, therefore, an integral component of global sustainability challenges (Sheehan 2007; see also Kenway and Lant 2015, Chap. 28, this volume).
Katherine A. Daniell, Jean-Daniel Rinaudo, Noel Wai Wah Chan, Céline Nauges, Quentin Grafton

Water Supply and Sanitation


Chapter 2. How Water Services Manage Territories and Technologies: History and Current Trends in Developed Countries

In recent decades urban water services have been confronted by new challenges questioning their sustainability. As detailed in previous chapters of this book, there have been environmental issues and climate change issues which require more efficient use of energy and water resources; and now the rise of ‘water poverty’ provokes renewed interest into social sustainability. At the same time, full cost recovery is broadly advocated, public subsidies are coming to an end, precisely when water services are facing calls for huge investment to renew their assets. Technical, economic, and social solutions have been provided by urban water industries and regulatory agencies, demonstrating that some of these challenges can be addressed. But the institutional and functional organisation of water services is also affected by these changes, which underlines the important governance issues that arise when crises occur and change is needed in urban water management.
Bernard Barraqué, Laure Isnard, Julien Souriau

Chapter 3. Coping with Extraneous Water in Sewerage Systems

The presence of extraneous water is a common deficiency for the sewerage systems nowadays. It may have different origin: surface or underground water, or water due to leaking water supply pipes. The amount depends mostly on the age and the level of maintenance of the sewer network. Defects of sewer pipes that allow infiltration may also allow exfiltration of sewer water into the soil and thus jeopardise the underground water quality. Both phenomena affect negatively the operation and maintenance of the sewer system and often result in higher energy demand or ineffective performance of the treatment facilities.
This chapter presents a simplified 5 steps methodology for estimating the presence and amount of extraneous water in sewerage systems, for which a WWTP has not been built yet. Other advantage is that the methodology does not require significant investments or extensive period of investigation. Its application is described in details for two case studies alerting the attention on the key factors that should be taken into account. Although the methodology carries some uncertainty the results obtained can indicate major problems and can help engineers to select technically and economically feasible solutions for rehabilitation of the municipal water supply and sewerage infrastructure.
Galina Dimova, Irina Ribarova, Franz de Carné

Chapter 4. Challenges for Water Supply and Sanitation in Developing Countries: Case Studies from Zimbabwe

Water supply and sanitation services in developing countries face a number of challenges which make it difficult for them to meet the Millennium Development Goals. The world population has increased by an average annual rate of 1.3 % since 1990 and currently stands at about 7 billion. Urbanisation around the world has increased from 43 % in 1990 to 51 % in 2010 and the rising trend is expected to continue. This urbanisation, which is highest in developing countries, has led to the mushrooming of informal settlements where water supply and sanitation services are virtually non-existent and waterborne diseases are prevalent. This chapter looks at the challenges for water supply and sanitation in developing countries and uses case studies and examples from Zimbabwe to illustrate typical problems. The problems include lack of investment in the water and sanitation sector, inappropriate technologies, ill-defined institutional frameworks, capacity limitations, and neglect of rural areas. Poor water supply and sanitation in Zimbabwe is typified by the cholera outbreak of 2008/09 which killed nearly 4,300 out of the 99,000 that were affected. The general conclusion of this chapter is that the problem of water supply and sanitation in developing countries requires innovative thinking as it impacts on other areas such as the food and energy sectors. The emphasis should be on appropriate technologies, particularly waterless toilets and natural sewage treatment systems. For water supply, focus should be on demand management and reduction of unaccounted-for water and innovative methods of enhancing revenue collection.
Innocent Nhapi

Chapter 5. The Challenges of Providing Water and Sanitation to Urban Slum Settlements in South Africa

Although the South African government has, since democratic transition, made considerable progress in providing water and sanitation, there are still many challenges, particularly in slum settlements where many residents lack access to clean water and safe sanitation. The country could experience serious social problems unless new policy and planning measures can be put in place, at both the national and local government levels, to address water and sanitation inadequacies. Already there are ominous signs that the country could face unrest as citizens vent their anger and frustration against poor basic services. The xenophobic attacks (2009/10), the ‘open toilet’ saga (2010/11), and the ‘feces protests’ (2013/14) (protests against the bucket toilet system in Western Cape) all bear evidence of the general discontent of urban people with poor service delivery. This paper discusses the challenges of providing water and sanitation to urban slum settlements in South Africa. The challenges include rising backlogs, poor cost recovery, a pervasive culture of non-payment for water services, and huge and unsustainable water deficits. These challenges hamper the ability of municipalities to provide sustainable and efficient services. Urgent attention to these problems is needed.
Ephias M. Makaudze, Gregory M. Gelles

Chapter 6. Integrating Water Quality into Urban Water Management and Planning While Addressing the Challenge of Water Security

In the face of growing water demand pressures, urbanisation, and climate change, freshwater resources are becoming scarcer and supply planners are turning to less traditional water sources, such as treated wastewater and urban run-off (stormwater), sources which may pose health risks to consumers. At the same time, traditional surface and groundwater resources are being subject to increased contamination, which contributes to water insecurity. How to address the water quality and public health dimension of urban water quantity challenges is emphasized in this chapter, especially through proper treatment and recycling of polluted run-off and wastewater, which, in the end, can achieve a two-fold benefit of increasing water supply (quantity) and improving the quality of available traditional freshwater resources. With the introduction of alternative sources however, and the delivery of fit-for-purpose water quality, it is crucial to both maintain and demonstrate the level of public health safety and protection in water supply. A systematic but flexible approach is needed to manage public health risks, either by framing and guiding the development of new supply schemes, or by assessing and validating the safety of existing schemes from contaminated sources. Quantitative Microbial Risk Assessment (QMRA) is a method that allows quantitative estimates to be made of microbial risks related to exposure of humans to water, either through drinking or other uses. In this chapter, the role of QMRA is described as a response to a 4-fold need, i.e. the need: (i) for technical guidance in the design of alternative supply schemes; (ii) for regulation to protect public health, both in traditional and alternative supply sources; (iii) for regulatory frameworks and institutions to enable innovation and development; and (iv) to assess new risks from innovative supply schemes and compare them to traditional water supply or other public health risks. Examples of water quality challenges in developing alternatives sources are given. Finally, the role of QMRA in balancing public health concerns with water availability issues and environmental, social, and economic factors in the decision-making process for water security planning is discussed.
Françoise Bichai, Patrick W. M. H. Smeets

Chapter 7. The Development of Private Bore-Wells as Independent Water Supplies: Challenges for Water Utilities in France and Australia

In developed countries, a number of factors are leading a growing number of households to drill private boreholes as independent water supplies. This chapter describes this phenomenon based on two case studies conducted in Southern France and Western Australia. It shows that, while the development of private wells was encouraged by the authorities in Perth, it is a major source of environmental, public health, economic and social concern for French water utilities. Household’s motivations to develop independent supply are then investigated. We finally discuss how water utilities need to adapt their management practices (setting tariffs, demand forecasting and resource protection) to take into account this phenomenon.
Jean-Daniel Rinaudo, Marielle Montginoul, Jean-François Desprats

Chapter 8. Inter-Basin Transfers as a Supply Option: The End of an Era?

This chapter discusses the evolving role of interbasin transfers (IBT) in urban water management. After providing an historical overview of IBT development, the chapter describes how IBTs are challenged by a change in the technological and socio-economic context. The emergence of alternative technologies, such as desalination, wastewater reclamation and reuse, or managed artificial groundwater recharge is reducing the attractiveness of IBTs. Water utilities are also becoming increasingly aware that water conservation programs can save volumes of water at a much cheaper cost than IBT. Various international examples are used to show that IBTs trigger increasing concerns from communities involved or affected, in particular related to the environmental impact on donor and receiving river basins, the economic impact on donor regions, the impact on local cultures and livelihoods, how costs and benefits are distributed (social justice), and issues related to public participation. The chapter concludes by looking ahead at new and more efficient uses of existing IBTs. As conjunctive use management approaches gain support, IBTs will be operated in conjunction with aquifer storage and recovery schemes. They will probably also support the development of emerging water markets, in particular during drought years.
Jean-Daniel Rinaudo, Bernard Barraqué

Chapter 9. Three Engineering Paradigms in the Historical Development of Water Services: More, Better and Cheaper Water to European Cities

The size and complexity of large cities creates the ‘urban water’ sustainability issue: where water transport and treatment technologies, public water services, including public water supply, sewage collection and treatment, and storm water control, had become the object of specific policies, separate from water resource allocation. Today, large metropolitan areas cannot take natural abundance for granted any more, and they need to protect and to manage water resources, if only to reduce the long term cost of transporting and treating water. In this chapter, we describe the historical development of water services in European metropolitan areas, placing the technological developments in their geographic, socio-economic, and political contexts. Our framework follows the successive contributions of three paradigms: civil engineering, sanitary engineering, and environmental engineering. Civil engineering has to do with the ‘quantity of water’, and it allows water to be moved in and out of cities, up hills, and under floors. Sanitary engineering has to do with ‘water quality’, and water treatment has given cities more freedom to take water from nearby rivers and to reduce impacts of sewer discharge. Lastly, environmental engineering has the potential to overcome supply-side shortcomings: it can use demand-side management, water conservation, water allocation flexibility; it can also provide an integrated approach to water services, water resources management, and land use policies.
Bernard Barraqué

Chapter 10. Investing in the Water Infrastructure of Tomorrow

The water sector today faces a complex range of challenges which mean it is increasingly important for water service providers (WSPs) to develop investment strategies that address growing uncertainty about operational, environmental, social, and economic constraints. Asset management provides an overarching framework within which infrastructure investment strategies can be formulated. While asset management is primarily concerned with maintaining service delivery, the concept can be extended to encapsulate broader sustainability objectives. In this chapter, we focus on the two main categories of capital investment: asset acquisition and asset renewals. Traditionally in the urban water sector, both types of investment have been undertaken within a framework focused on water supply, sewage disposal, and stormwater management separately. Increasingly, however, integrated urban water management (IUWM) concepts are being applied to address the broader sustainability, liveability, and productivity objectives of communities. Progress in implementing change is, however, constrained by lock-in effects of legacy infrastructure and associated institutional arrangements. Nevertheless, innovation at the scheme and project level still occurs. This leads to an overarching process of system hybridisation, the key factors behind this process being the normative values and risk perception of decision makers and other stakeholders. Two case studies are presented to illustrate the type of analysis that is undertaken to support investment decisions leading to this hybridisation. The first involves a traditional like-for-like pipe renewal, whereas the second relates to asset acquisition aligned with broader IUWM concepts. Both case studies highlight that the relative worth of an investment depends strongly on how broader environmental and social factors are considered. These are increasingly influencing infrastructure investment decisions in the transition to more sustainable urban water management.
David R. Marlow, David J. Beale, Stephen Cook, Ashok Sharma

Water Demand and Water Economics


Chapter 11. Long-Term Water Demand Forecasting

This chapter reviews existing long term water demand forecasting methodologies. Based on an extensive literature review, it shows that the domain has benefited from contributions by economists, engineers and system modelers, producing a wide range of tools, many of which have been tested and adopted by practitioners. It illustrates, via three detailed case studies in the USA, the UK and Australia, how different tools can be used depending on the regulatory context, the water scarcity level, the geographic scale at which they are deployed and the technical background of water utilities and their consultants. The chapter reviews how practitioners address three main challenges, namely the integration of land use planning with demand forecasting; accounting for climate change; and dealing with forecast uncertainty. It concludes with a discussion of research perspectives in that domain.
Jean-Daniel Rinaudo

Chapter 12. The Use of Non-pricing Instruments to Manage Residential Water Demand: What Have We Learned?

Given the high costs of developing new water supply projects, there is increased interest in demand-side management (DSM) involving measures aimed at promoting residential water conservation. In this chapter, we focus on the main DSM policy options not related to pricing and assess their impact on residential water consumption based on a survey of empirical studies. We look at the advantages and disadvantages of each policy in detail, analysing the relations and interactions between pricing and non-pricing policies.
Maria A. Garcia-Valiñas, Roberto Martínez-Espiñeira, Hang To

Chapter 13. The Social Determinants of Water Consumption in Australian Cities

Most cities in Australia periodically face acute shortages of potable water. In most of them the supply of potable water comes from sequestering supplies from eco-systems away from but close to that in which the urban development occurs. The response usually is to try to husband the water sequestered and stored in dams by managing the demand to ‘get’ through the dry periods.
Patrick Troy

Chapter 14. Non-household Water Demand: The Industrial and Commercial Sectors

Whereas households are the largest water users in most urban centres, non-residential water use accounts for as much as 30–40 % of a typical water utility’s total output. Thus, for many water utilities facing the rising costs of developing new sources for potable water, improvements in water use efficiency in the industrial and commercial sector are seen as a virtual new source. The purpose of this chapter is to briefly examine what is known regarding the economics of water use by industry and commerce and to investigate how this knowledge could be used to promote efficient water use. The chapter begins by illustrating some of the important characteristics of industrial and commercial water use. Of particular interest is the role of energy consumption in affecting demand for water, as well as the ways in which this sector’s water use differs from its residential counterpart. The chapter then considers economic techniques for modeling and measuring industrial and commercial water use. An important output from these modeling efforts is an estimate of price elasticity of a firm’s demand for intake water. The chapter concludes by presenting several case studies that demonstrate water agencies’ efforts to promote water conservation among industrial and commercial users.
Steven Renzetti

Chapter 15. Integrating Social Aspects into Urban Water Pricing: Australian and International Perspectives

Over the last decade, society’s aspirations towards affordable urban water have been overtaken by other objectives – economic efficiency, financial sustainability, and environmental conservation. This chapter provides an overview of how social equity can be built into water pricing principles, processes, and outcomes. Examples are given, and analyses are made of water affordability in Australian capital cities from 1995/96 to 2011/12 and compared with the values of water concessions given to disadvantaged people by state governments. We conclude that social equity and affordability factors can be successfully integrated into the price structure of urban water and doing so has particular advantages.
Noel Wai Wah Chan

Chapter 16. Does Residential Water Use Depend on Water Quality? Some Answers from a French Case Study

We examine the possible link between residential water consumption and quality of the water, both raw water and tap water. We first survey the existing literature on residential water use and its relation to water quality. An empirical analysis using French data is then provided. Our findings suggest that the quality of water at the tap, in particular its bacteriological quality, is a strong predictor of residential water consumption.
Arnaud Reynaud, Marian A. Garcia-Valiñas

Chapter 17. A Simulation Model for Understanding the Consequences of Alternative Water and Wastewater Tariff Structures: A Case Study of Fayoum, Egypt

Egypt has successfully made the transition to high quality piped water services. Currently 98 % of urban households and 96 % of rural households have access to piped water services, primarily through private connections for the exclusive use of household members. Now that water supply coverage with piped networks has been largely accomplished, the water and wastewater utility companies in Egypt face new challenges. One of the most pressing is the need to generate revenues that are sufficient for a financially sustainable future. Today most of the financial resources needed by the water supply sector come from government development grants which finance capital expenditures and some subsidies to cover operation and maintenance costs. The Egyptian government wants to reduce this financial support and encourage the water and wastewater sector to gradually become financially self-sufficient. In this chapter we present a simulation model that was designed to assist the Egyptian Water Regulatory Agency to better navigate the tariff reform process. We simulate the effects of alternative tariff structures on customer water use, which in turn affects utility revenues and costs. The different tariff structures are compared in terms of their achieving the following four objectives: (1) financial cost recovery, (2) economic efficiency, (3) fairness and equity, including affordability, and (4) tariff simplicity.
Céline Nauges, Dale Whittington, Mohamed El-Alfy

Chapter 18. Managing Water Variability Issues

Despite the growing use of manufactured sources, urban centres still predominantly rely on climate-dependent water sources. In many cases, the supply is subject to significant variability and uncertainty, and there is concern that climate change will increase this. Variability and uncertainty create a number of significant issues that need to be managed. This chapter reviews the issues and considers alternative approaches to managing them.
The chapter begins with a general discussion of the features of urban water supply and the issues created by variability and uncertainty, many of which are common to other infrastructure industries. These include the issues of pricing and optimal timing of ‘lumpy’ investments when there is uncertainty.
This chapter then focuses on a key feature of many urban water systems: that of large, cheap storage. Storage has implications for both the problem of lumpy investments and how uncertainty is managed. These implications are examined, including consideration of how storage affects investment and pricing decisions.
An emerging issue is that of water security. The risk of a major urban centre running out of water is a key driver of urban water policy. Often there is a lack of clarity about how water security goals and criteria are established. This chapter considers the government’s role in providing water security and how this may change as diversity of supply increases.
This chapter also considers governance arrangements in the face of uncertainty. Commonly, urban water augmentation decisions, pricing, and operational decisions are centrally managed by government agencies and/or government-owned organisations. However, markets offer a potential alternative that is more responsive to changed conditions and needs. The potential for markets to help deal with the issue of uncertainty is explored.
Hugh Sibly, Richard Tooth

Chapter 19. Volumetric Water Pricing, Social Surplus and Supply Augmentation

We evaluate the welfare losses of undertaking water supply augmentation in Sydney, Australia with a fixed, regulated water price given weather variability. Stochastic dynamic programming is used to determine dynamically efficient water prices and to estimate the losses in social surplus from premature water supply augmentation. Results show that premature water supply augmentation under the base case reduces the net present value (NPV) of the welfare of households by more than $A 3 billion, or some $A 1,900 NPV per household. While the findings are specific to Sydney, our modeling is of general interest because it could be employed to avoid costly and premature supply augmentation elsewhere.
Quentin Grafton, Long Chu, Tom Kompas, Michael Ward

Water Governance and Integrated Management


Chapter 20. Governance and Regulation of the Urban Water Sector: Quoi de Neuf?

This chapter analyses three themes in the evolution of urban water sector governance and regulation in developed countries over the last few decades. The first theme is a reduction in direct government management and control of the urban water systems through a process we describe as devolution. The second theme is the growing sophistication and use of policy tools for regulating the urban water sector, in part as a result of the devolution and separation of ownership, operation, and regulation. The third theme is the re-emergence of broader social and environmental concerns in the water sector, prompting a variety of government responses. The themes are necessarily high level, one reason being that, historically, they have appeared in a variety of forms and under a diversity of governance, regulatory, and environmental circumstances. We draw on evidence from across the developed world and use case studies from Australia and France to illustrate how the themes have manifested.
Walter Reinhardt, Lætitia Guérin-Schneider

Chapter 21. Public–Private Partnerships and Their Ownership in the Urban Water Sector

This chapter explores the experience of public–private partnerships (PPPs) in the provision of urban water and sanitation services. We show that there exists a wide range of PPPs available to the water industry. Across the public and the private parties, these PPPs typically differ in their allocation of decision prerogatives, risks, and revenues. The main question we address is the relationship between the ownership of the PPP and the performance of water services in terms of their technical and cost efficiency, water price, and access to water and sanitation services.
Arnaud Reynaud

Chapter 22. Issues of Governance, Policy, and Law in Managing Urban–Rural and Groundwater–Surface Water Connections

Urban water systems increasingly are seen as one part of a complex web of diverse water sources and uses. Urban water managers can now rarely focus on one water source, or on water supply reliability alone, without considering social and environmental effects. Water laws and institutional arrangements can facilitate urban water suppliers recognizing and benefiting from connections and interactions in two core areas: between groundwater and surface water sources, and between urban and rural water supplies. This chapter will review, at a high level, how water laws and institutions can address these core areas of interaction, and encourage associated innovations. It also reviews challenges that remain in these areas. First, it discusses how water laws can provide for conjunctively managing groundwater and surface water sources through regulatory structures for managed aquifer recharge for urban supply, whether the source water derives from the urban area itself (for example, stormwater or treated wastewater), or out-of-district sources under water banking arrangements. Second, it examines how law can support connections between urban and rural water supplies, through water trading and source swapping, and agricultural use of urban wastewater. To illustrate these issues, it uses examples from Australia and the western United States—areas in which urban water suppliers face the common challenges of population growth, water scarcity, and increasing environmental demands.
Rebecca Nelson, Heather N. Bischel, Richard G. Luthy, Barton H. Thompson

Chapter 23. Integrated Management of Urban Water Supply and Water Quality in Developing Pacific Island Countries

Urban areas in Pacific island countries (PICs) use varied sources of water and have very diverse water supply challenges. They share, however, common, concerns particularly over the adequacy and continuity of supply, water quality, sustainability of supply systems, protection of water sources, control of increasing demand, and reduction of water losses. The issues are complex and are not generally amenable to simple solutions. While some urban water problems in PICs are similar to those in developing countries elsewhere, others are unique to the Pacific. These require an understanding of the geographic, climatic, hydrologic, social, cultural, and economic contexts. A central premise here is that improvements in water supply and quality in urban centres in PICs require robust but locally appropriate institutions and enhanced capacities while maintaining or improving the integrity of water sources and dependent ecosystems.
Here we discuss a broad range of interacting factors: water governance, assessment and monitoring, management and protection of water sources, management of demand and losses, capacity building, empowerment of communities, and coping with climate variability and climate change. These together with limited capacities and resources, specific cultural contexts and local institutions, and the diverse and dispersed nature of island communities, require special attention by policy makers and practioners. The strengths of local communities and extended families, particularly their natural resilience to change, provide a good basis for implementing water reforms and for adapting to development pressures, climate variability, and climate change – provided the interaction between subsistence traditions and customary rights on the one hand and urban modes and values on the other can be managed.
Ian White, Tony Falkland

Chapter 24. The “Renaturation” of Urban Rivers: The Case of the St Charles River in Quebec

Urban rivers are central to city planning policies. The aim is to clean up rivers and encourage the return of citizens to their banks. The challenge is to align the interests of developers, water users, and politicians. In the case of the St Charles River, the City of Quebec has combined a large urban renewal program with a project to restore the aquatic ecosystem. This project provides an example of how cities in Quebec are now playing a larger role in water management than they did previously. This paper suggests that the restoration of urban rivers should be associated with a project for economic and social development. Furthermore, restoration (called in this paper “renaturation”) is not enough: cities must also fight against urban sprawl and more effectively protect their freshwater supplies and wetlands.
Alexandre Brun

Chapter 25. Adapting to Climate Change in Urban Water Management: Flood Management in the Rotterdam–Rijnmond Area

Many large coastal cities are located in deltas, which makes them vulnerable to floods. In many cities flood damage has increased due to increases in population and assets, and this process is expected to continue. At the same time, climate change will cause floods to occur more often in many rivers and deltas due to higher discharges and sea level rise. These trends call for the development and implementation of new technologies and strategies in flood risk management. This call is also acknowledged in the Netherlands, a country that has a strong history of relying on structural measures. The city of Rotterdam includes many unembanked areas, large parts of which will be redeveloped in the near future. Current practice is to elevate all unembanked areas to a 1 in 4,000 years flood level. This is not only very costly, but also causes problems when an area is redeveloped in phases, or when existing buildings will remain as both cause unwanted elevation differences and differences in flood protection. Rotterdam is therefore looking for adaptive (non-structural) measures to decrease flood damage in these areas. Such measures are presently little used in the Netherlands. One key question is how these new measures fit in within current policies, laws, and regulations in Rotterdam. This chapter describes measures studied for a case study area in Rotterdam, gives an analysis of the policies, laws, and regulations relating to these measures, and examines the implications for urban flood management. Our research shows that, in principle, the rules do allow for implementation of adaptive measures. It is, however, problematic how these measures can be enforced, and this weakness can cause problems, e.g. when not all waterfront buildings are dry-proofed. Better communication of flood risks is recommended, as this will increase awareness and preparedness, which in turn might lead to a higher implementation rate of adaptive measures.
M. van Vliet, J. C. J. H. Aerts

Chapter 26. Transboundary Urban Water: The Case of Singapore and Malaysia

Singapore is a small and populous country, and to sustain its people and economy it requires resources originating from an area many times its size for food, water, energy, and other resources. This paper considers the unique situation of transboundary sharing of water supplies between Singapore and Malaysia, a case in which the parties do not share the same water basin. Singapore has to buy water from Malaysia in order to meet its domestic and economic needs, but many Malaysian rivers are polluted and water demand in Malaysia itself has increased substantially because of population growth and changes in lifestyle. Consequently, Malaysian authorities face difficulties in meeting their own country’s needs. During past dry spells in Malaysia, Singapore became a target of resentment when Malaysians experienced water shortage and rationing. Attempts by Singapore to negotiate a new water agreement for water supply beyond 2061 have been rejected by the Malaysian government. This situation has, since the 1990s, led Singapore to pursue other sources to achieve water self-sufficiency. To meet its water demand, Singapore has embarked on the use of ‘NEWater’, which is recycled treated sewerage effluent, and on the desalination of seawater.
Yue Choong Kog

Chapter 27. The Opportunities and Challenges of Implementing ‘Water Sensitive Urban Design’: Lessons from Stormwater Management in Victoria, Australia

Responding to pressure on the natural and built environments from population growth, the need for safe and secure water to support resilient and liveable communities, and the need to adapt to increased climate risk and variability, many cities around the world have sought new ways to develop, manage and sustain their urban environments. Indeed, in recent years, three important and related concepts have emerged in relation to cities and urban development: first, the need to design cities so as to minimise the impact of climatic events on populations, infrastructure and the environment; second, the need to optimise human consumption of scarce natural resources, particularly land, water, energy and nutrients; and third, the need to protect and where possible conserve the natural environment in and between cities. Over time, these concepts have evolved into a variety of different concepts, approaches and ‘visions’ to guide future land use development. One such concept is ‘water sensitive urban design’ (WSUD), a term whose definition varies but which is nevertheless now readily accepted internationally as a core aspiration of urban development (Wong and Brown 2011).
Karen Hussey, Esther Kay

Chapter 28. How Does Energy Efficiency Affect Urban Water Systems?

Urban water management influences significant energy use. In Australian cities, water management directly and indirectly uses 13 % of Australia’s electricity and 18 % of its natural gas. Collectively, it accounted for 8 % of the country’s primary energy use in 2007, approximately five times the direct energy use of the agricultural sector, excluding transport. Water-related energy consumption in cities includes energy used in the provision, consumption, and disposal of water. About 10 % is direct energy use by utilities. The majority of the figure relates to water used in homes, business, and government. There is scope for urban water management to reduce water-related energy use, particularly if strategies actively target the large amount of energy associated with water use.
A ‘metabolic’ approach to water mass balance can be used to account for all the inputs and outputs of water flowing through cities. The metabolic balance includes rainfall, stormwater run-off, and percolation to groundwater. It is very distinct to the supply–demand balance typically applied in urban water management. Application of such a balance to four Australian cities in 2004–05, a period of critical water shortage, demonstrated that significant volumes of water passed through them unaccounted for and unused. These unused and untracked local water resources have the potential to provide new supply options; however, they also require substantial efforts to harness effectively. Because urban water systems are completely interconnected with the cities they service, urban water problems cannot be solved in isolation of the city or its planning. Transitioning urban water strategies to become ‘energy sensitive’ therefore has wide implications for urban planning, funding, and management. Likewise, it has other consequences for our cities: wider use, understanding, reporting, and benchmarking of urban metabolism and the water–energy nexus could change how we think about our cities and their water systems. We could actually view our cities as sources of water, and could view our urban water systems as a partial solution to energy and greenhouse gas emission problems. Such thinking could lead to considerable changes in physical systems and institutional structures. As pointed out by Abel Wolman in 1965, there is no shortage of water or energy, but finding new solutions requires long-term thinking.
Steven J. Kenway, Paul A. Lant


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