Climate Change Adaptation in the Water Sector

Fulco Ludwig, Pavel Kabat, Henk van Schaik, Michael van der Valk

• Publisher: Routledge
• Year: 2012
• ISBN:
  9781136569876
• Edition: 1
• Topic: Sciences physiques
• Subtopic: Météorologie et climatologie

Today's climate variability already has a large impact on water supply and protection. Millions of people are affected every year by droughts and floods. Future climate change is likely to make things worse. Many people within the water sector are aware that climate change is expected to have serious consequences for water resource management, but they are unsure how to incorporate climate information into their management structures. Providing a compendium of specific strategies, Climate Change Adaptation in the Water Sector is the first book to show students and professionals in the water sector how to adapt to climate change and variability. It enables advanced students, managers, decision-makers and other practitioners to feel comfortable in analysing and using climate data within the water sector. The book consists of two parts: the first describes the general issues and is written mainly by the editors of the book, while the second part contains specific case studies drawn from a wide range of contrasting countries: Australia, Germany, The Netherlands, the Philippines, South Africa, Thailand and Yemen. Published in association with the Co-operative Programme on Water and Climate, NeWater, UNESCO and WATCH (Water and Global Change)

1

Introduction

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Fulco Ludwig, Peter Droogers, Michael van der Valk,
Henk van Schaik and Pavel Kabat

Climate variability results in significant impacts on water availability and safety. Every year, millions of people are affected by droughts and floods. In the future, climate change is likely to increase both the number and magnitude of hydrological extremes.

The importance of climatic variability and change, resulting in long-term, far-reaching and widespread impacts on livelihoods, is clearly acknowledged by most scientists and policy-makers. Not as widely recognized, however, are changes in attitude towards water management that are required to successfully adapt to the impacts and challenges associated with climate change. Many people within the water sector are aware that climate is affecting water resources management, but do not know how to integrate climate change information within water management. Planners and developers find it hard to use climate scenarios and projections because of their inherent levels of uncertainty.

The main purpose of this book is to inform water managers and decision-makers about climate change, its impacts and how to adapt to these changes. It offers water professionals a comprehensive introduction to climate science, climate projection methodologies, their relevance and limitations for water management. It offers guidance and examples on how water management can and should reduce its vulnerability to future changes in the climate system. During the last decade, the availability of information and tools in relation to managing climate variability and change has rapidly expanded. After reading this book, water professionals and advanced students should feel much more comfortable in using climate information in decision support and in managing water resources. Readers will also become more familiar with the institutional challenges that are involved in climate change adaptation.

In the past, water managers have generally been conservative with regards to climate change. Examples in this book show how water managers struggle with using state-of-the-art information from new developments such as seasonal climate forecasting or climate change scenarios. Traditionally, the design of water management systems has been based on historical climate and hydrological data, assuming stationarity of weather and water system behaviour. However, the forecasted changes in climate no longer allow for such assumptions, and historical data are no longer adequate to meaningfully plan for variability and extremes. The impact of climate change on hydrological systems is expected to be such that new approaches are necessary to better ensure that investments will not be lost. This book provides initial guidelines and examples of how water management could be altered in order to reduce its vulnerability to climatic changes. In these chapters, the design of infrastructure is discussed alongside how institutions are adapting to new approaches that use climate change information for decision-making on investments and resource management. This book informs water managers on how to move from using only historical data to a decision-making system that includes information on climate variability and change. The information presented here could also be used to train the next generation of water managers in becoming familiar with these new approaches.

Climate Change Adaptation in the Water Sector is divided into two parts. Part I describes theoretical and methodological aspects of the climate system, and what options are available for the water sector to adapt to climate change and to cope with climate variability. In Part II, case studies on adaptation to climate change from all over the world focus on a variety of issues.

The book starts with an introduction on the climate system. Recent changes in climate are described and the science of predicting climate variability at a seasonal timescale is discussed. The last part of Chapter 2 focuses on climate projections at the decadal timescale. Chapter 3 focuses on the use of climate change scenarios. It describes issues such as regional climate change scenarios, and how tailor-made climate scenarios can be developed and used in different sectors. Chapter 4 provides a brief and general description of the impacts of recent and future climate change on water resources management. It discusses the impacts of droughts, floods and water quality and some possible institutional impacts.

Before discussing how water management can be adapted to cope with climate change, we take a look, in Chapter 5, at how the water sector has managed climate variability in the past. Current practices of using historical climate data for the design of water infrastructure are discussed and the concept of integrated water resources management and its relation to climate are introduced. Large seasonal variation in rainfall is a major challenge for water managers. At the start of the season, it is often unclear how much water will be available for different users. Seasonal forecasts can be used to partly reduce uncertainties so that water management can be improved on a seasonal basis. Chapter 6 discusses how to use seasonal forecasts and includes several practical examples.

Adaptation to climate change is discussed in Chapter 7. The major focus is on risk management, as well as issues such as dealing with uncertainty and adaptive management. The final chapter in Part I, Chapter 8, introduces the concept of climate-proofing, which has gained significant support during recent years. The idea is not to eliminate all climate risks but to use a combination of hard and soft measures to minimize and spread risks to acceptable levels. It is argued that climate change is not only a threat, but can also be seen as an opportunity.

Climate change adaptation is a relatively new challenge and most projects are still in their infancy: the effectiveness of practices, whether precautionary or proactive, is yet to be assessed. As a result, only a few well-documented cases of adaptation can be found. For this book we have collected a set of eight informative cases from different countries describing how people are adapting to climate change.

The first case study in Part II, Chapter 9, describes the management of floods and disasters in Thailand with a special emphasis on social justice. Starting with an evaluation of historical policies and practices, it draws inferences about the key challenges posed by altered flood regimes resulting from climate change and adaptation policies. These underline the importance of a policy of adaptation that emerges from contested and changing perceptions and experiences of risks. The main conclusion from this case study in Thailand is that persistent social injustices could be made worse by both inaction and misguided climate change adaptation policies. The chapter ends with a strong message that we should not wait for more catastrophic confirmations of climate change: there are many actions today that would benefit disadvantaged and vulnerable groups which do not need climate change as their justification.

The second case study from The Netherlands (Chapter 10), focuses on flooding as well. However, the socio-economic contexts of Thailand and The Netherlands are so disparate that adaptations in both cases are quite different. In the past, water management in The Netherlands was dominated by controlling fluctuations in water levels in order to protect the 50 per cent of the country located below sea level. Climate change, however, requires another approach towards water, and a policy shift from ‘fighting against water’ to ‘living with water’ has been advocated in the case study. The main issues required for this policy shift are discussed in Chapter 10. The most important message is that water management and spatial planning should be considered in a far more integrated way. A more collective approach is also required where various governmental bodies agree to act jointly to adapt to climate change in three focal areas: urban and rural development; areas close to rivers; and coastal areas. Besides this so-called practical approach where direct actions are taken, a forward-looking approach has been initiated. The latter includes two main activities: first, to initiate several large-scale integrated research programmes funded by the Dutch government; and, second, to develop joint strategies on ‘adaptation spatial planning and climate’ (ARK) between various ministries, provinces, municipalities, water boards, the research community and the private sector. The chapter concludes that this transition in management cannot be completed in the short term; it is a gradual and iterative process in which all parties must reset their visions on dealing with problems and solutions.

The Yemen case study in Chapter 11 addresses water shortages, with special emphasis on groundwater resources and the impact of climate change. The chapter starts by stating that groundwater systems are comparatively resilient to short-term and seasonal shortage of rainfall, but are very vulnerable to longer-term changes. Groundwater is often, especially in arid regions, the most reliable source of water – if not the only one – for domestic water supply and irrigation of crops. The case study explores to what extent groundwater in alluvial aquifers in arid regions may be affected by climate change during the 21st century. One of the main conclusions is that coping with the consequences of degenerating groundwater resources in Yemen's alluvial aquifers is difficult. Technical measures, such as artificial recharge and improved water-use efficiencies, will not be sufficient to overcome the negative impacts of climate change. Improved rigorous water resource planning and management is necessary. The study concludes that unconventional and innovative measures need to be developed – including control of demographic pressure and transition to a less water-dependent economy. The challenges as described in the chapter are not specific to Yemen; the overall conclusions may be extrapolated to alluvial aquifers elsewhere in arid zones. The mechanisms are similar: ever-increasing human pressure on scarce and dwindling groundwater resources with its related set of complex problems, escalated by climate change.

Chapter 12 focuses specifically on drinking water and the impacts of, and adaptation to, climate change. Umgeni Water in South Africa serves about 5 million people in Durban, Pietermaritzburg and their surroundings with a total of 340 million cubic metres of potable water annually. The utility's water resources assessment techniques consist of two, quite distinct, assessments. The first one, described as the current situation, is based on short timeframe analyses where current water demands are balanced against current supply availability, leading to possible changes to the system operation rules. The second one, the future situation, is based on long timeframe analyses where future water demands are balanced against future supply availability. Climate change would impact most significantly upon the latter type of assessment. It is interesting that climate change was never high on the agenda of the utility. A workshop on climate change, involving the top management of the utility, proved to be a milestone: consideration of climate change impacts were elevated to a higher level based on a better understanding of the topic. Currently, they rank climate change as the third highest risk associated with the management of the natural environment. Lessons learned from the case study are that Umgeni Water has developed a process to assess the hydrological impacts of climate change, and they are currently at the early stages of implementing this process. However, completing the process and tabling the current results is not considered to be the final answer to the problem as the process is dynamic and further analyses will be required as driving factors change.

Chapter 13 also addresses drinking water as the main topic, but now in the Australian context. The case study describes the adaptation measures taken by the Metropolitan Water Supply for Perth in Western Australia. Restrictions on urban water use have been imposed frequently in the past and Water Corporation Perth is beginning to incorporate climate change within its planning processes by a combination of increasing the supply and simultaneously trying to decrease the demand. However, the study claims that underpinning decision-making with information obtained from the latest developments in climate science is still in its infancy. Despite this lack of knowledge, Australia's urban water industry is responding to the stressors of climate change by changing its operating environment, developing or at least considering additional and alternative sources of water (e.g. water reuse and desalination), and being sensitive to the views and concerns of its customers. The described adaptive responses of water planners in Perth may set a pragmatic precedent for water planners elsewhere. The nature of their adaptive response will be shaped by the physical, hydrological, socio-economic and political settings that they confront and the financial resources available. Perth has also benefitted from a coastal location (making seawater desalination a feasible option), ready access to shallow as well as deep groundwater supplies, and an extensive array of dams and pipelines facilitating inter-basin transfer of water supplies.

Chapter 14 includes water economics as a means of assessing and adapting to the impact of climate change. The focus of this case study is the Berg River Basin in the Western Cape Region of South Africa. The basin is an economically important water supply system, providing the bulk of the water for household, commercial and industrial use in Cape Town. It also provides irrigation water to the lower part of the basin to cultivate roughly 15,000ha of high-value crops. The Berg River Dam, with its 130 million cubic metres of storage capacity, is expected to be operational some time during the period of 2008 to 2010. It is, however, unclear to what extent reservoir operation is consistent with expected climate change. Based on a combined water–climate–economic policy-planning model, a set of scenarios is analysed, resulting in alternative uses of the water from the Berg River Dam. The study describes the technical details of the model used to evaluate the impact of climate change. Moreover, the model has been used to assess the most optimal water resources allocation and reservoir operational rules to maximize economic returns of water under various climate change scenarios. The most relevant conclusions from the model evaluations are that climate change will reduce total water availability by 11 per cent in the near future and by 17 per cent in the distant future, and that climate change will reduce basin-wide welfare by between 6.3 per cent and 8.4 per cent in the near future, and by between 11.5 per cent and 15.6 per cent in the distant future, depending upon the water allocation option that will be implemented. This case study can serve as a typical example of how such a policy-planning tool could be used in other cases where water allocation issues should be assessed in the context of climate change.

The seventh case study, in Chapter 15, emphasizes the institutional adaptation to climate change for the Elbe Basin in Germany. The study investigates whether the current river basin management institutions in the Elbe Basin allow for adaptation to climate change impacts. It considers institutions as a broad set of rules, decision-making procedures and programmes. The current institutional adaptive capacity to climate change impacts in the Elbe Basin was based on the perceptions of 11 interviewed experts. In-depth interviews were conducted in spring 2007 with representatives from different organizations at international, national and sub-national levels. The focus was on a so-called analytical framework of seven elements as criteria for adaptation to climate change. These seven elements were essential for the entire study and comprise: (i) availability and communication of information; (ii) polycentric governance; (iii) participation; (iv) sectoral integration; (v) openness for experimentation; (vi) flexibility; and (vii) planning horizons, political support and economic resource. The study provides a general overview of the current situation of institutional adaptation in the German Elbe Basin. The main conclusion is that adaptation is still at an early stage, while a relatively high awareness of the issue already exists. Remarkably, the information on, and discussion about, adaptation is not as prominent as the current discussions concerning climate change mitigation. However, at the same time, adaptation strategies already exist at lower organizational levels of water management. One of the main conclusions from the study is that effective adaptation to climate change requires leadership and support by political decision-makers.

The last case study described in this book, in Chapter 16, originates from the Philippines where the use of seasonal climate forecasts to manage a reservoir system is explored. The study concentrates on the Angat Reservoir, which provides the primary source of water for Metropolitan Manila. The Philippines has an extremely variable climate largely due to the El Niño Southern Oscillation (ENSO), which can serve at the same time as the source of predictability and seasonal climate forecasts of inflows to the Angat Reservoir. The study shows that seasonal climate forecasts can be used to dynamically change the reservoir operational rules such that it reflects the probability of dry conditions in a given year instead of the long-term probability. Based on the conditions of the ocean and atmosphere, it can be determined that the probability of dry conditions is greater than or less than the long-term average. In years when the probability of dry conditions is less than average, more water could be released. However, the actual implementation of these seasonal climate forecasts in reservoir operation depends not only upon the potential benefits, but also upon the institutional context. The study concludes that the potential to apply seasonal climate forecas...

Table of contents

• Front Cover
• Half Title
• Title Page
• Copyright
• Contents
• List of figures, tables, boxes and plates
• List of contributors
• Acknowledgements
• List of acronyms and abbreviations
• 1 Introduction
• PART I: CLIMATE CHANGE AND WATER
• PART II: CASE STUDIES
• Index