3
Berlin Heidelberg New York Barcelona Hongkong London Milan Paris Santa Clara Singapore TokyoThe Council Members (as on 1.6.1997) Prof. Dr. Friedrich O. Beese
Agronomist: Director of the Institute for Soil Science and Forest Nutrition in Göttingen
Prof. Dr. Klaus Fraedrich
Meteorologist: Professor of Meteorology at the University of Hamburg
Prof. Dr. Paul Klemmer
Economist: President of the Rhine-Westphalian Institute for Economic Research in Essen
Prof. Dr. Dr. Juliane Kokott (vice chairperson)
Lawyer: Professor of German and International Comparative Public Law, European and International Law at the University of Düsseldorf
Prof. Dr. Lenelis Kruse-Graumann
Psychologist: Professor of Psychology (specialist in environmental psychology) at the University of Hagen
Prof. Dr. Ortwin Renn
Sociologist: Academy of Technology Impact Assessment in Baden-Württemberg, Professor of Sociology at the University of Stuttgart.
Prof. Dr. Hans-Joachim Schellnhuber (chairperson)
Physicist: Director of the Potsdam Institute for Climate Impact Research (PIK) and Professor of Theoretical Physics at the University of Potsdam
Prof. Dr. Ernst-Detlef Schulze
Botanist: Director of the Max-Planck-Institute for Biogeochemistry, Jena
Prof. Dr. Max Tilzer
Limnologist: Professor of Limnology at the University of Konstanz
Prof. Dr. Paul Velsinger
Economist: Professor of Political Economy at the University of Dortmund, specializing in regional economics
Prof. Dr. Horst Zimmermann
Economist: Professor of Political Economy at the University of Marburg, specializing in public finance
German Advisory Council on Global Change
World in Transition:
Ways Towards Sustainable Management of
Freshwater Resources
Annual Report 1997
with 76 illustrations
123
German Advisory Council on Global Change (WBGU) Secretariat at the Alfred Wegener Institute for Polar and Marine Research Columbusstraße
D-27568 Bremerhaven Germany
http://www.wbgu.de
Translation: Tim Spence, Bremen
Cover design: E. Kirchner, Heidelberg, using the following illustrations Niagara Falls, USA
Abdullah irrigation canal, Jordan Water vendor, Marrakech, Morocco Irrigation with fossil water, Disi, Jordan Mendenhall glacier, Alaska, USA Flotsam, Salamis, Greece
(all photos: Meinhard Schulz-Baldes) Copy deadline: July 1997
ISBN 3-540-64351-6 Springer-Verlag Berlin Heidelberg New York ISSN 1431-1666
CIP-Data applied for
Die Deutsche Bibliothek – CIP-Einheitsaufnahme
World in transition: ways towards sustainable management of freshwater resources / German Advisory Council on Global Change.
[Transl.: Tim Spence]. - Berlin; Heidelberg; New York; Barcelona; Hongkong; London; Milan; Paris; Singapore; Tokyo: Springer 1999 (Annual report/ German Advisory Council on Global Change; 1997) Dt. Ausg. u.d.T.: Welt im Wandel: Wege zu einem nachhaltigen Um- gang mit Süßwasser.
ISBN 3-540-64351-6
Deutschland / Wissenschaftlicher Beirat Globale Umweltveränderungen:Annual report / German Advisory Council on Global Change.
- Berlin; Heidelberg; New York; Barcelona; Hongkong; London; Milan; Paris; Singapore; Tokyo: Springer
Früher im Economica-Verl., Bonn; Dt. Ausg. u.d.T.: Deutschland / Wissenschaftlicher Beirat Globale Umweltveränderung: Jahresgutach- ten 1997. World in transition: ways towards sustainable management of freshwater resources. - 1999
This work is subject to copyright. All rights are reserved, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitations, broadcasting, reproduction on microfilm or in any other way, and storage in data banks. Duplication of this publication or parts thereof is permitted only under the provisions of the German Copyright Law of Septem- ber 9. 1965, in its current version, and permission for use must always be obtained from Springer-Verlag. Violations are liable for prose- cution under the German Copyright Law.
The use of general descriptive names, registered names, trademarks, etc. in this publication does not imply, even in the absence of a spe- cific statement, that such names are exempt from the relevant protective laws and regulations and therefore free general use.
© Springer-Verlag Berlin Heidelberg 1999 Printed in Germany
This Report would not have been possible without the committed and untiring effort of the staff of the Council Members and of the Council’s Secretariat in Bremerhaven. The Council wishes to express its fullest gratitude to all those research fellows who participated in the work of the Council when this re- port was written:
Prof. Dr. Meinhard Schulz-Baldes (Director, Sec- retariat, Bremerhaven), Dr. Carsten Loose (Deputy Director, Secretariat, Bremerhaven), Dr. Frank Bier- mann (Secretariat, Bremerhaven), Dr. Arthur Block (Potsdam Institute for Climate Impact Research), Dipl.-Geogr. Gerald Busch (University of Göttin- gen), Dr. Ursula Fuentes Hutfilter (Secretariat, Bre- merhaven), Dipl.-Psych. Gerhard Hartmuth (Uni- versity of Hagen), Dr. Dieter Hecht (University of Bochum), Andreas Klinke, M.A. (Academy for Tech- nology Impact Assessment, Stuttgart), Dr. Gerhard Lammel (Max Planck Institute for Meteorology, Hamburg), Referendar-jur. Leo-Felix Lee (Universi- ty of Heidelberg), Dipl.-Ing. Roger Lienenkamp (University of Dortmund), Dr. Heike Mumm (Alfred Wegener Institute, Bremerhaven), Dipl.-Biol. Marti- na Mund (University of Bayreuth), Dipl.-Volksw.
Thilo Pahl (University of Marburg), Dr. Benno Pi- lardeaux (Secretariat, Bremerhaven), Dipl.-Biol.
Helmut Recher (Max Planck Institute for Limnolo- gy, Plön).
The Council also wishes to thank the staff mem- bers who were responsible for the compilation and editing of this Report:
Vesna Karic-Fazlic (Secretariat, Bremerhaven), Ursula Liebert (Secretariat, Bremerhaven), Martina Schneider-Kremer, M.A. (Secretariat, Bremer- haven).
Moreover, the Council acknowledges the support of the researchers of the projects „Questions“ (Pots- dam Institute for Climate Impact Research) and
„Syndrome Dynamics“ (BMBF). Both projects pro- vided invaluable help in the further elaboration and refinement of the syndrome approach:
Dipl.-Geogr. Martin Cassel-Gintz (Potsdam Insti- tute), Dr. Jochen Dehio (RWI Essen), Dipl.-Chem.
Jürgen Kropp (Potsdam Institute), Dr. Matthias
Lüdeke (Potsdam Institute), Dipl.-Phys. Oliver Moldenhauer (Potsdam Institute), Dr. Gerhard Petschel-Held (Potsdam Institute), Dr. Matthias Plöchl (Potsdam Institute), Dr. Fritz Reusswig (Pots- dam Institute), Dr. Hubert Schulte-Bisping (Univer- sity of Göttingen).
The Council also owes its gratitude to the impor- tant contributions and support by other members of the research community. This Report builds on com- ments and reports in particular from:
Prof. Dr. J. Alcamo, Dr. P. Döll, F. Kaspar and S.
Siebert, University of Kassel, Science Center on Ecosystem Research: „Global Mapping of Regional Water Vulnerability“.
Dr. G. Bächler, Director, Swiss Peace Foundation, Bern, Switzerland: „Das Atatürk-Staudammprojekt am Euphrat-Tigris unter besonderer Berücksichti- gung der sicherheitspolitischen Relevanz zwischen den Anliegerstaaten Türkei, Syrien und Irak“.
Dr. N. Becker and O. Leshed, University of Haifa, Israel: „Using Economic Incentives to Mitigate a Po- tential Water Crisis“.
Prof. Dr. E. Brown Weiss, Georgetown University Law Center, Washington, DC, USA: „Prevention and Solutions for International Water Conflicts: the Great Lakes (USA-Canada)“.
Prof. Dr. M. Exner, University of Bonn, Hygienic Institute: personal communication.
Dr. W. Grabs, Bundesanstalt für Gewässerkunde, Global Runoff Data Center, Koblenz: personal com- munication.
Prof. Dr. H. Graßl: World Climate Research Pro- gramme, Geneva: personal communication.
Dr. M. Heimann and Dr. E. Röckner, Max Planck Institute for Meteorology, Hamburg: „Modellierung des Wasserdargebots“.
Dipl.-Forstw. J. Herkendell, Ministry of Environ- ment, Regional Planning and Agriculture of the Land North-Rhine Westphalia, Düsseldorf: „Lite- raturübersicht zu allgemeinen gesundheitlichen Aspekten von Wasserproblemen“.
Prof. Dr. D. Ipsen, University of Kassel, Working Group on Empirical Planning Research: „Kultur-
Acknowledgment
angepaßte Maßnahmen für einen veränderten Um- gang mit Wasser“.
Prof. Dr. med. J. Knobloch, University of Tübin- gen, Institute for Tropical Medicine: „Die Ausbrei- tung wasserverursachter Infektionskrankheiten“.
S. Kuhn, ICLEI European Secretariat, Freiburg:
„Internationale Übersicht über Aktivitäten zur Lokalen Agenda 21“.
Dr. K. Lanz, Hamburg and Prof. Dr. J. S. Davis, ETH Zürich, Switzerland: „Wasserkulturen der Welt im Vergleich – Eine Analyse westlicher Wasserwerte im Lichte fremder Kulturen“.
Prof. S. McCaffrey, University of the Pacific, Mc- George School of Law, Sacramento, USA: personal communication.
Prof. Dr.-Ing. Dr.-Ing. e.h. E. J. Plate, University of Karlsruhe, Institute for Hydrology and Water Man- agement: „Wasser und Katastrophen (IDNDR)“.
Prof. Dr.-Ing. U. Rott and Dipl.-Ing. R. Minke, University of Stuttgart: „Wassertechnologien:
Grundlagen und Tendenzen“.
Prof. Dr.-Ing. Dr. rer. pol. K.-U. Rudolph and Dipl.-Ök. Th. Gärtner, Consultants for Water Engi- neering and Management, Witten: „Die deutsche Wasserver- und -entsorgung im internationalen Ver- gleich. Schwächen und Stärken eines zukünftigen
‘deutschen Modells’ sowie umweltpolitische Export- möglichkeiten“.
Prof. Dr. R. Sauerborn, Heidelberg Clinic, Dept.
for Tropical Hygiene: personal communication.
Prof. Dr. U. Shamir, Water Research Institute, Technion Israel Institute of Technology, Haifa, Israel:
„Sustainable Water Management“.
Dr. H.-H. Stabel, Betriebs- und Forschungslabor Zweckverband Bodensee-Wasserversorgung, Über- lingen: „Vergleichende Bewertung der interna- tionalen und nationalen Standards für Nutzwasser (Trinkwasser, Irrigation, Industrie, Bergbau u.a.)“.
Prof. Dr.-Ing. D. Stein, University of Bochum, Fakultät für Bauingenieurwesen: „Moderne Leitungsnetze als Beitrag zur Lösung der Wasser- probleme von Städten“.
Prof. Dr. D. A. Tarlock, Chicago Kent College of Law, Chicago, USA: „The Use of Watermarkets to Reallocate Water to New Demands“.
Cand. iur. D. Thieme, University of Düsseldorf, Faculty of Law: „Implementierung der Klimarah- menkonvention: Vorschläge für ein Zusatzpro- tokoll“.
Dr.-Ing. M. Voigt, University of Dortmund, Facul- ty of Regional Planning: „Was ist die heutige Wasserkultur in Agglomerationsräumen der Bun- desrepublik Deutschland und welche Restriktionen und Möglichkeiten zur Entwicklung einer neuen nachhaltigen Wasserkultur lassen sich benennen?“
Dr. R. Wiedenmann, Zürcher Kantonalbank, Switzerland, and Dr. A. Sanchez, Santa Cruz: „Bedin- gungen, Leistungsfähigkeit und Grenzen von Genossenschaftslösungen für landwirtschaftliche Bewässerungssysteme“.
A 1 2 B C
1 2 3 4 D
1 2 3 4 5 E
1 2 F G H I
Executive Summary 1
Summary of individual chapters 3 Key recommendations for action 13 Introduction 17
Five years after the UN Conference on Environment and Development in Rio de Janeiro 23
Introduction 25
International policymaking in response to Global Change 26 Local government implementation of AGENDA21 36
Summary and prospects 41 Focus: Water 43
The freshwater crisis: Basic elements 45
Water in the global network of interrelations – the causal web 114 Global water problems and their causes 121
Key issues 204
Solutions to the global water crisis 262 Recommendations 333
Key recommendations for research on freshwater resources 335 Key recommendations for policy action on water resources 342 References 349
Glossary 371
The German Advisory Council on Global Change 377 Index 381
Outline of Contents
Contents
A 1 2 B C
1 2 2.1 2.1.1 2.1.2 2.2 2.2.1 2.2.2 2.2.3 2.3 2.3.1 2.3.2 2.3.3 2.4 2.5 2.5.1 2.6 2.6.1 2.6.2 2.6.3 2.7 2.7.1 2.7.2 2.7.3 3 3.1 3.2 3.2.1 3.2.2
Executive Summary 1
Summary of individual chapters 3 Key recommendations for action 13 Introduction 17
Five years after the UN Conference on Environment and Development in Rio de Janeiro 23
Introduction 25
International policymaking in response to Global Change 26 Atmosphere 26
The Montreal Protocol 26
UN Framework Convention on Climate Change 26 Hydrosphere 27
Protection of the Seas from Land-based Pollution 27 Overfishing 27
The International Tribunal on the Law of the Sea in Hamburg 28 Biosphere 28
Convention on Biological Diversity 28 Intergovernmental Panel on Forests 29
Negotiations on Plant Genetic Resources for Food and Agriculture 30 Lithosphere/Pedosphäre 30
Population 31
UN Conference for Population and Development (Cairo) 31 Social organization 32
United Nations World Conference on Women (Beijing) 32
United Nations Conference on Human Settlements (Habitat II) 33 World Conference on Human Rights 33
Economy 34
General Agreement on Tariffs and Trade / World Trade Organization 34 United Nations World Food Summit (Rome) 34
United Nations World Summit for Social Development (Copenhagen) 35 Local government implementation of AGENDA21 36
Importance of local-level political processes for sustainable development 36 The LOCALAGENDA21 concept 36
Local government participation in the LA21 process 37 LA21 activities – an international comparison 37
X
LA21 initiatives in Germany 38
Towards sustainability with LA21 – Potentials and barriers 39 Summary and prospects 41
Focus: Water 43
The freshwater crisis: Basic elements 45 Water functions 45
Natural functions 46 Life-sustaining function 46 Habitat function 46 Regulatory functions 46 Cultural functions 47
Water as habitat and its importance for neighboring environments 48 Standing waters 48
Running waters 49 Soil and groundwater 49 Wetlands 51
Biodiversity of limnic ecosystems 52 Recommended action and research 53 The hydrological cycle 55
Water balance 55
The hydrological cycle in the atmospheric energy balance 56 Interactions with the atmosphere 58
Radiation, water vapor and clouds 59 Atmospheric chemistry and aerosols 59 Cryosphere and ocean 60
Vegetation in arid and semi-arid regions 60 Interactions with vegetation 61
Impacts on water balance 61 Impacts on water quality 64
Model: hydrological cycle in the present and future 65
Comparison between observations and simulations of present climate 66 Simulated changes in the hydrological cycle under CO2doubling 66
Current and future water withdrawals by agriculture, industry and for domestic use 69
Definitions and data situation 69 Present rates of water withdrawal 69 Future withdrawal trends 75
Water quality 81
Inventorying of water quality 83 Precipitation 83
Surface waters 85 Groundwater 90
Monitoring water quality 91 Water quality standards 91 Drinking water 92
Water in agricultural production 94 Recommended research and action 95 Water and disasters 96
Introduction 96
Flood damage trends 97
From heavy rains to flood damage 98 Classification of different flood types 99 3.2.3
3.2.4 4 D
1 1.1 1.1.1 1.1.1.1 1.1.1.2 1.1.1.3 1.1.2 1.2 1.2.1 1.2.2 1.2.3 1.2.4 1.2.5 1.2.6 1.3 1.3.1 1.3.2 1.3.3 1.3.3.1 1.3.3.2 1.3.3.3 1.3.3.4 1.3.4 1.3.4.1 1.3.4.2 1.3.5 1.3.5.1 1.3.5.2 1.4 1.4.1 1.4.2 1.4.3 1.5 1.5.1 1.5.1.1 1.5.1.2 1.5.1.3 1.5.1.4 1.5.2 1.5.2.1 1.5.2.2 1.5.3 1.6 1.6.1 1.6.1.1 1.6.1.2 1.6.2
1.6.3 1.6.3.1 1.6.3.2 1.6.3.3 1.6.4 1.6.4.1 1.6.4.2 1.6.5 2 2.1 2.2 2.2.1 2.2.2 3 3.1 3.1.1 3.1.2 3.1.3 3.1.4 3.2 3.2.1 3.2.2 3.3 3.3.1 3.3.1.1 3.3.1.2 3.3.2 3.3.2.1 3.3.2.2 3.3.2.3 3.3.2.4 3.3.3 3.3.3.1 3.3.3.2 3.3.3.3 3.4 3.4.1 3.4.2 3.4.2.1 3.4.2.2 3.4.2.3 3.4.2.4 3.4.2.5 3.4.3 3.4.3.1 3.4.3.2 3.4.4 3.4.4.1 3.4.4.2
Effects of climate change on floods 101 Observed precipitation and runoff trends 102
Other possible changes to flood hydrology due to climate change 103 Modeling 104
Management and control of flood risks 105 Determination of flood risks 106
Managing flood risks 108 Research recommendations 113
Water in the global network of interrelations – the causal web 114 Trends in the hydrosphere 114
Global mechanisms of the water crisis 116 Impacts on hydrosphere trends 116
Effects of hydrosphere trends on other spheres 119 Global water problems and their causes 121
The criticality index as a measure of the regional importance of the water crisis 121
Modeling withdrawal trends 122 Modeling water availability 123
Water-specific problem-solving capacity 124 Formulation of a criticality assessment 125
Syndromes as causal webs of relevance to the water crisis 131 Relevance of individual syndromes for water resources 131 Systematic ranking of the syndromes 137
The Green Revolution Syndrome: Environmental degradation through the intro- duction of inappropriate farming methods 139
Definition 139 Description 139 Major features 140
General description of the syndrome 140 Syndrome mechanism 140
Syndrome intensity, indicators 148 Syndrome linkages and interactions 151 General recommendations for action 152 Water-specific syndrome description 155 Water-specific syndrome mechanism 155 Water-specific network of interrelations 155 Water-specific recommendations 158
The Aral Sea Syndrome: environmental degradation due to large-scale damage to natural landscapes 163
Definition 163
Water-specific syndrome mechanism 165
Core trends at the people-environment interface 165 Driving factors 165
Impacts on the ecosphere 167 Impacts on the anthroposphere 169 Syndrome coupling 171
Examples 171 Aral Sea 171
The Three Gorges project 173
Indirect measurement of syndrome intensity 176
Measurement of the core trend “changes in surface runoff” 177 Measuring vulnerability 177
XI
Intensity 180
Recommended action 180
Reducing the disposition to the Aral Sea Syndrome 180 Evaluation of large-scale water development projects 181
Mitigating the impacts of existing large-scale water development projects 183 Research recommendations 184
The Favela Syndrome: Uncontrolled urbanization, impoverishment and threats to water resources and the environment in human settlements 184
Definition 185
General syndrome diagnosis 186
Rural exodus, decline of traditions and uncontrolled urbanization 186 Failure of governance, growing significance of the informal sector and exclusion 190
Water-specific syndrome description 193 Disparities between withdrawal and supply 193 Water pollution and eutrophication 193 Lack of infrastructure and its consequences 194 Water-specific threats to human health 195 Water-centered network of interrelations 195
Dynamic measure of intensity of the Favela Syndrome 195 Syndrome cure 197
General recommendations for action 197 Water-specific recommendations for action 199 Key issues 204
International conflicts 204
Basic elements of conflict analysis 204 Pathways to conflict management 205 Regional water conflicts 205
The Ataturk Dam on the Tigris-Euphrates 205 The Jordan basin 209
The Gabcikovo Dam on the River Danube 210 The Great Lakes in North America 212
Degradation of freshwater resources as a global problem 213 Regional water conflicts as a threat to world security 213 Freshwater resources as part of the world natural heritage 214 Inland waters and marine pollution 214
The “human right to water” 215 Summary 215
Spread of waterborne diseases 216 Diseases related to water use 216 Use of contaminated drinking water 217
Water-based hosts and carriers of infectious diseases 220 Trends in the spread of waterborne infections 222 Need for action and recommendations 225 Water and food 229
Historical background 229 Population growth and food 229
Food and water consumption: current situation and a look into the future 233 Recommended action 234
Research recommendations 237
Degradation of freshwater ecosystems and neighboring habitats 237 Salinization and desiccation 238
Acidification 240
Eutrophication and pollution 240 3.4.4.3
3.4.5 3.4.5.1 3.4.5.2 3.4.5.3 3.4.6 3.5 3.5.1 3.5.2 3.5.2.1 3.5.2.2 3.5.3 3.5.3.1 3.5.3.2 3.5.3.3 3.5.3.4 3.5.3.5 3.5.3.6 3.5.4 3.5.4.1 3.5.4.2 4 4.1 4.1.1 4.1.2 4.1.3 4.1.3.1 4.1.3.2 4.1.3.3 4.1.3.4 4.1.4 4.1.4.1 4.1.4.2 4.1.4.3 4.1.4.4 4.1.5 4.2 4.2.1 4.2.1.1 4.2.1.2 4.2.2 4.2.3 4.3 4.3.1 4.3.2 4.3.3 4.3.4 4.3.5 4.4 4.4.1 4.4.2 4.4.3 XII
XIII
4.4.4 4.4.5 4.4.6 4.4.7 4.4.8 4.5 4.5.1 4.5.1.1 4.5.1.2 4.5.1.3 4.5.2 4.5.3 4.5.3.1 4.5.3.2 4.5.4 4.5.5 5 5.1 5.1.1 5.1.2 5.1.3 5.2 5.2.1 5.2.1.1 5.2.1.2 5.2.1.3 5.2.1.4 5.2.1.5 5.2.2 5.2.3 5.3 5.3.1 5.3.2 5.3.2.1 5.3.2.2 5.3.2.3 5.3.3 5.4 5.4.1 5.4.1.1 5.4.1.2 5.4.1.3 5.4.1.4 5.4.2 5.4.2.1 5.4.2.2 5.4.2.3 5.4.3 5.4.3.1 5.4.3.2 5.4.3.3
Introduction of non-native species 242 Overfishing of inland waters 243
Declining area and quality of inland waterbodies due to direct intervention 244 Impacts of the loss and degradation of wetlands 244
Recommended research and action 249
Water technologies: Basic principles and trends 249 Water supply 250
Water collection 250 Water distribution 251 Water treatment 251 Water use 255 Water disposal 256
Water collection and transport 256 Water purification 257
Development trends and research needs 259 Recommended action 260
Solutions to the global water crisis 262
Guidelines for the “sound management of water resources” 262 The guiding principle developed by the Council 262
Normative guidelines for sound management of water resources 263
The model as reflected in recent trends in the fields of international resource pol- icy and international law 264
Sociocultural and individual conditions for water resource management 265 Water cultures: Sociocultural contexts of water resource management 265 The scientific and technological dimension 265
The economic dimension 267
The legal and administrative dimension 268 The religious dimension 269
The symbolic and esthetic dimension 270 Water scarcity and behavior 271
Water pollution and behavior 274
Principles and instruments of sustainable water management: Environmental education and public discourse 276
Environmental education activities aimed at sound management of water re- sources 276
Communication and discourse 281 Bases of discursive communication 281 Communicative forms of orientation 281
Implementation and application of discursive procedures 282 Recommendations 285
Economic approaches to the sustainable management of water resources 286 Special characteristics of water 286
Multifunctionality and the diverse valuation of water resources 287 Divergent properties of water as an economic commodity 292 The regional character of most water problems 295
Growing importance of water efficiency 296 Solving the allocation problem 298
Basic options 298
Water markets as the solution 300
Securing minimum water requirements 303
Water resource management in Germany and the USA – a comparison 304 Preliminary remarks 304
Water resource management in Germany 305 Water resource management in the USA 305
XIV
Recommendations 307
Legal principles and instruments pertaining to water resource management 309 Introduction 309
Water resource management in Germany 310 Legal regulation of water utilization in Germany 310 Public supply of drinking water 311
International water law 311
Rules of general international law regarding the use of transboundary water- courses 312
Recent treaties at regional level 314
Progress in the work of the International Law Association 315
UN Convention on the Law of the Non-Navigational Uses of International Wa- tercourses 316
Strengthening international mechanisms for the prevention of conflicts 318 Intensifying international cooperation for the protection of freshwater resources 320
“Global Consensus” on freshwater resources 320 Functions 321
Possible institutional arrangements 323 Summary 325
Instruments 326
Preservation of valuable biotopes (World Heritage) 326 Water supply and wastewater disposal 326
Health 327
Irrigation and food 328
Disaster prevention and control 329
Resolving conflicts at national and international level 329 Recommendations 333
Key recommendations for research on freshwater resources 335 Sectoral analysis of the system as a whole 335
Specification and application of the guiding principle 336 Specific applications of the guiding principle 338
Integrated system analysis 340
Key recommendations for policy action on water resources 342 Elements of a global water strategy 342
Specification of the paradigm 342
Compliance with and application of the model 343
Selected key recommendations for preventing a worldwide freshwater crisis 345
References 349 Glossary 371
The German Advisory Council on Global Change 377 Index 381
5.4.4 5.5 5.5.1 5.5.2 5.5.2.1 5.5.2.2 5.5.3 5.5.3.1 5.5.3.2 5.5.3.3 5.5.3.4 5.5.4 5.5.5 5.5.5.1 5.5.5.2 5.5.5.3 5.5.5.4 5.6 5.6.1 5.6.2 5.6.3 5.6.4 5.6.5 5.6.6 E
1 1.1 1.2 1.3 1.4 2 2.1 2.2 2.3 2.4
F G H I
Box D 1.1-1 Box D 1.2-1 Box D 1.3-1 Box D 1.3-2 Box D 1.4-1 Box D 1.6-1 Box D 3.2-1 Box D 3.3-1 Box D 3.3-2 Box D 3.3-3 Box D 3.5-1 Box D 3.5-2 Box D 4.1-1 Box D 4.2-1 Box D 4.2-2 Box D 4.3-1 Box D 4.3-2 Box D 4.4-1 Box D 4.4-2 Box D 4.4-3 Box D 4.5-1 Box D 5.2-1 Box D 5.2-2 Box D 5.2-3 Box D 5.2-4 Box D 5.2-5 Box D 5.2-6 Box D 5.3-1 Box D 5.3-2 Box D 5.3-3 Box D 5.3-4 Box D 5.4-1 Box D 5.4-2 Box D 5.4-3 Box E 2-1
Boxes
Functions of water 46
Lake Baikal: One of the most important natural laboratories of evolution 54 Runoff variability of selected African rivers 57
The stomata of plants 62 Fossil water resources 70
Non-technological methods of flood prevention and control 109 Overview of Syndromes of Global Change 132
The green revolution in India: Water problems 146
Participative methods of data collection and project planning in development cooperation 156
International legal aspects of food security 161 Examples of the Favela Syndrome 187
Methodology for selecting appropriate methods of wastewater treatment 201 Game-theoretical modeling of conflict situations 206
Rats and disease 222 Malaria on the rise 224
Aquaculture – the growing importance of a traditional production method 235 Irrigation systems of the Nabateans 236
The introduction of non-native fish species and the impacts: two case studies 243
The Pantanal – one of the largest wetland areas in the world – is endangered 246
The Ramsar Convention 248
Adapted technologies for water supply and disposal in developing countries 260
Manifestations and meanings of water 266 Water as a “culture-forming element” 267
Water without users: irrigation facilities in Peru 268 Kenya: From the commons to private property 269 New Zealand: The water culture of the Maori 270
Water-consuming modes of behavior of private households 273 Effectiveness of psychosocial interventions 278
The concept of “efficient water use” in Frankfurt am Main 280 Women and water in developing countries 281
Experience with discursive procedures in the environmental sector in Germany and abroad 283
Economic valuation of agricultural water use 289
Categories of value not normally manifested as willingness to pay 291 Important categories of goods 293
Global Code of Conduct for Implementing the Right to Water (“World Water Charter”) 346
Tab. D 1.2-1 Tab. D 1.3-1 Tab. D 1.3-2 Tab. D 1.4-1 Tab. D 1.4-2 Tab. D 1.4-3 Tab. D 1.4-4 Tab. D 1.4-5 Tab. D 1.4-6 Tab. D 1.4-7 Tab. D 1.4-8 Tab. D 1.4-9 Tab. D 1.4-10 Tab. D 1.4-11 Tab. D 1.5-1 Tab. D 1.5-2 Tab. D 1.5-3 Tab. D 1.5-4 Tab. D 1.5-5 Tab. D 1.5-6 Tab. D 1.5-7 Tab. D 1.5-8 Tab. D 1.5-9 Tab. D 1.5-10 Tab. D 1.5-11 Tab. D 1.5-12 Tab. D 1.6-1 Tab. D 3.1-1 Tab. D 3.1-2 Tab. D 3.1-3 Tab. D 3.3-1 Tab. D 3.4-1 Tab. D 3.4-2 Tab. D 3.5-1
Global occurrence of wetlands 51 Continental water balances 55
Continental intercomparison of observed and modeled annual precipitation 65
The world’s major aquifers 70
Agriculture’s share of global water withdrawals, 1900–1995 71 Annual, continental water withdrawals by agriculture 71 Water withdrawals by industry 73
Growth of water consumption by industry in the USA 73 Water recycling rate 75
Drinking water consumption per person and day in Germany, 1995 75 Annual domestic water withdrawals, by continent 77
Basic assumptions about water use in the agricultural, industrial and domestic sectors for the L, M and H scenarios of the WaterGAP model 79
Growth of water withdrawals by industry in selected countries 80 Growth of domestic water withdrawals (1980s to 2000) 80 Factors affecting water quality 82
Typical concentrations of the major ions in continental and oceanic precipitation 84
Biodegradable organic substance, non-biodegradable substance and oxygen concentration in European rivers and worldwide 87
Metal concentrations in the world’s waterbodies 88
Classification of surface waterbodies according to trophic level 89 Trophic levels in lakes and reservoirs worldwide 89
Possible levels of complexity for a general monitoring of running waters program 90
Comparison of selected parameters for drinking water standards 93 Water quality assessment for irrigation 94
Recommended maximum concentrations of toxic substances in irrigation water for continuous irrigation systems 95
Suitability of saline water for cattle 95
Maximum values recommended by the National Academy of Sciences, USA, for metals and salts in water drunk by cattle 95
Number of people affected by natural disasters, 1991–1995 97 Ideal-typical conceptions of the economy-ecology relationship 124 Definition of the vulnerability index 125
Number and percentage of people affected by the global water crisis 129 Mean annual consumption of nitrogen fertilizer in the green revolution countries, 1994 157
Sediment loads of selected rivers 168
Historical streamflow maxima in the Yangtze River and extreme flood levels during the 20th century 174
Inhabitants of favelas 186
Tables
Summary comparison of the formal and informal sectors 191 Trends in structure of persons employed in the cities of Latin America, 1950-1989 192
Water supply to urban households (study of about 1,000 households) 195 Wastewater treatment in humid to semi-arid regions 201
Water-related diseases 217
Salinization phenomena caused directly or indirectly by natural and anthropogenic factors, their regional distribution and forecast trends 239 Global loss of wetlands 245
Equipment and facilities for harvesting and distributing water 250 Processes for water purification and wastewater treatment 252
Distribution of responsibilities in alternative approaches to water supply:
Evaluation of case studies 297
Estimated average total annual cost (1993–2000) for implementing Chapter 18 of AGENDA21 323
Tab. D 3.5-2 Tab. D 3.5-3 Tab. D 3.5-4 Tab. D 3.5-5 Tab. D 4.2-1 Tab. D 4.4-1 Tab. D 4.4-2 Tab. D 4.5-1 Tab. D 4.5-2 Tab. D 5.4-1 Tab. D 5.5-1 XVIII
Fig. C 2-1 Fig. D 1.1-1 Fig. D 1.2-1 Fig. D 1.2-2 Fig. D 1.2-3 Fig. D 1.3-1 Fig. D 1.3-2 Fig. D 1.3-3 Fig. D 1.3-4 Fig. D 1.3-5
Fig. D 1.3-6 Fig. D 1.3-7 Fig. D 1.3-8
Fig. D 1.3-9
Fig. D 1.4-1 Fig. D 1.4-2 Fig. D 1.4-3 Fig. D 1.4-4 Fig. D 1.4-5 Fig. D 1.4-6 Fig. D 1.4-7 Fig. D 1.5-1 Fig. D 1.5-2
Linkages between the Biodiversity Convention and other global environmental regimes 29
Global distribution of water resources 45
Diagram of a river course, showing zoning of fish fauna, physical gradients and oxygen profile 50
Number of species of terrestrial and aquatic vertebrates 52
Factors contributing to North American freshwater fish extinction 53 Global hydrological cycle: reservoirs, fluxes and typical residence times 56 Seasonal runoff and interannual variance of the Senegal, 1903–1973, and of the Congo, 1912–1983 57
a) Percentage absorption in the atmosphere, b) global radiative and energy balance 58
Diagram of stomatal structure showing gas and water exchanges 62
Global distribution of annual precipitation. a) Observed data, b) simulation of today’s climate, c) simulation of a climate with double CO2equivalent, d) difference between model simulations of the future and present day climates 66
Global distribution of annual runoff. Difference between model simulations of the future and present day climates 67
Global distribution of annual evapotranspiration. Difference between model simulations of the future and present day climates 67
Difference between the model simulations of today’s climate and climate with double CO2equivalent. a) Annual soil water totals, b) number of months of aridity stress in which soil water concentration falls below a critical threshold 67
Global distribution of climate zones according to Köppen. a) Observations, b) simulation of today’s climate, c) simulation of a climate with double CO2 equivalent, d) difference between model simulations of the future and present day climates 68
a) Water withdrawals by agriculture, 1995, b) per capita water withdrawals by agriculture, 1995 72
a) Water withdrawals by industry, 1995, b) per capita water withdrawals by industry, 1995 74
a) Water withdrawals for domestic use, 1995, b) per capita water withdrawals for domestic use, 1995 76
Relative growth and decline in total water withdrawals as a result of population growth, 1995–2025 77
Relative growth and decline in water withdrawals by agriculture, 1995–2025 78 Relative growth and decline in water withdrawals by industry, 1995–2025 81 Relative growth and decline in domestic water use, 1995–2025 82
The sequence of water quality issues arising in industrialized countries, 1850–present 83
Threat of waterbody acidification 84
Figures
Sediment transported by rivers. Absolute sediment yield and relative sediment yield per unit area of catchment area 86
Salt concentrations in different freshwater bodies worldwide 87
Flood damage: Costs to the economy and insured damages caused by major floods in the 1960–1996 period 97
Global distribution of flood risk 98 Parts of a watershed 99
Cascade of flood risk 102 A risk management system 106
Flood risk exposure, shown by the isolines for water levels during extreme flood events with different return periods 107
Elements of a flood control and protection system 108
Benefits of advance warning periods in the case of dam breaks 108 The Water-centered Global Network of Interrelations 115
The Water-centered Global Network of Interrelations: Impacts 117
Assessment matrices. a) Low substitutability, b) high substitutability of natural by economic capital stock 126
Scenario II and difference in 2025. a) Criticality index in 1995, assuming low substitutability, b) change in criticality index to 2025, assuming the middle scenario for water withdrawals and the IS92a IPCC forecast for economic growth and population trends 127
Scenario I and difference in 2025. a) Criticality index in 1995, assuming low substitutability, b) change in criticality index to 2025, assuming the middle scenario for water withdrawals and the IS92a IPCC forecast for economic growth and population trends 128
Change in the number of people affected by severe or very severe water crisis between 1995 and 2025 130
Significance of the individual syndromes in terms of their contribution to the water crisis 138
Network of interrelations for the Green Revolution Syndrome, Stage I (ca. 1965–1975) 141
Network of interrelations for the Green Revolution Syndrome, Stage II (ca. 1975–1985) 142
Network of interrelations for the Green Revolution Syndrome, Stage III (ca. 1985–today) 143
Specific indicators of the green revolution. a) Absolute areal productivity growth of cereal crops, 1960–1990, b) average food supply deficit in 1961, c) per capita cereal production in 1991, d) relative growth in cereal yield remaining in the country 148–149
Occurrence of the green revolution 150
Occurrence of the Green Revolution Syndrome 151 Syndrome links over time 153
Network of interrelations for the Aral Sea Syndrome 166 Discharge of the River Colorado downstream from the dams 169 Total inflows and volume of the Aral Sea (1930–1985) 172
a) Number of dams in a province or country in relation to the total river length in the respective region, b) dam impact indicator, i.e. expected number of upstream dams per km3of annual flow volume 178
a) Vulnerability to severe damage to nature and people due to the construction of large dams, b) intensity of the Aral Sea Syndrome 179
Network of interrelations for the Favela Syndrome 189
Age-adjusted mortality rates by socio-environmental zones in Accra and São Paulo, 1991-1992 196
Intensity of the Favela Syndrome. Explanations in the text 197 A typology of conflicts 205
Fig. D 1.5-3 Fig. D 1.5-4 Fig. D 1.6-1 Fig. D 1.6-2 Fig. D 1.6-3 Fig. D 1.6-4 Fig. D 1.6-5 Fig. D 1.6-6 Fig. D 1.6-7 Fig. D 1.6-8 Fig. D 2-1 Fig. D 2-2 Fig. D 3.1-1 Fig. D 3.1-2
Fig. D 3.1-3
Fig. D 3.1-4 Fig. D 3.2-1 Fig. D 3.3-1 Fig. D 3.3-2 Fig. D 3.3-3 Fig. D 3.3-4
Fig. D 3.3-5 Fig. D 3.3-6 Fig. D 3.3-7 Fig. D 3.4-1 Fig. D 3.4-2 Fig. D 3.4-3 Fig. D 3.4-4
Fig. D 3.4-5 Fig. D 3.5-1 Fig. D 3.5-2 Fig. D 3.5-3 Fig. D 4.1-1 XX
Fig. D 4.2-1 Fig. D 4.2-2 Fig. D 4.2-3 Fig. D 4.2-4 Fig. D 4.2-5 Fig. D 4.3-1 Fig. D 4.3-2 Fig. D 4.3-3 Fig. D 4.3-4 Fig. D 4.3-5 Fig. D 4.3-6 Fig. D 4.3-7 Fig. D 4.3-8 Fig. D 4.4-1 Fig. D 4.5-1 Fig. D 4.5-2 Fig. D 5.1-1 Fig. D 5.4-1 Fig. D 5.4-2
a) Population without access to clean drinking water, b) population without access to sanitation facilities 216
a) Population with access to clean drinking water, b) infant mortality 218 Outbreaks of cholera in 1995 219
Outbreaks of dengue and yellow fever in 1995 220 Incidence of malaria 221
Growth of world population 230
Increases in cereal crop yields since 1950 231
World grain production and growth of per-capita production, 1960–1994 231 Comparison of grain production levels in Europe and Africa (1960–1994) 232 Calorie consumption and diets in different world regions 232
Growth in areas used for cereal crops and irrigated farming 233 Growth of aquaculture production 235
Percentage of protein supply obtained from fish 235 Map of the Pantanal 246
Process diagram for a surface water treatment plant 255
Process diagram for a municipal sewage treatment plant with extensive removal of carbon, nitrogen and phosphorus compounds 257
The “guardrails” philosophy advocated by the WBGU 263
Marginal yield value for water in Arizona cotton farming (1975 and 1980) 289 Water markets. Explanations in the text 301
XXI
Acronyms and Abbreviations
ADB AIDS BGBl BGW BMBF BML BMZ BOD BVerfGE CBD CBO CCD CDC CFC CFS CGE CGIAR CIMMYT CITES CMS COD CSD DAAD DALY DDT DFG EC ECE ECHAM4-
OPYC ECMWF ECOSOC EIA EPI ESCAP
Asian Development Bank
Acquired Immune Deficiency Syndrome
Bundesgesetzblatt [Official German Collection of Legal Documents and Treaties]
Bundesverband der Deutschen Gas- und Wasserwirtschaft [Federal Association of German Gas and Water Works]
Bundesministerium für Bildung, Wissenschaft, Forschung und Technologie [Federal Ministry of Education, Science, Research and Technology]
Bundesministerium für Ernährung, Landwirtschaft und Forsten [Federal Ministry of Food, Agriculture and Forestry]
Bundesministerium für wirtschaftliche Zusammenarbeit und Entwicklung [Federal Ministry for Economic Cooperation and Development]
Biological Oxygen Demand
Bundesverfassungsgerichtsentscheidung [Judgment of the German Federal Constitutional Court]
Convention on Biodiversity Community Based Organization
United Nations Convention to Combat Desertification in those Countries Experiencing Serious Drought and/or Desertification, particularly in Africa Centers for Disease Control and Prevention (USA)
Chlorofluorocarbon
Committee on World Food Security (FAO) Compagnie Générale des Eaux (France)
Consultative Group on International Agricultural Research (USA) Centro Internacional de Mejoramiento de Maiz y Trigo (Mexico)
Convention on International Trade in Endangered Species of Wild Fauna and Flora
Convention on the Conservation of Migratory Species of Wild Animals Chemical Oxygen Demand
Commission on Sustainable Development (UN) Deutscher Akademischer Austauschdienst [German Academic Exchange Service]
Disability-Adjusted Life Years Dichlordiphenyltrichlorethan
Deutsche Forschungsgemeinschaft [German Research Foundation]
European Communities/Community Economic Commission of Europe (UN)
Coupled Atmosphere-Ocean Climate Model (MPI on Meteorology and German Climate Computing Center)
European Centre for Medium-Range Weather Forecast (UK) Economic and Social Council (UN)
Environmental Impact Assessment Expanded Programme of Immunization
Economic and Social Commission for Asia and the Pacific
European Union
Food and Agriculture Organization of the United Nations Framework Convention on Climate Change
Fourth World Conference on Women
United Nations General Assembly Official Records Günedogu Anadolu Projesi
General Agreement on Tariffs and Trade General Circulation Models
Gross Domestic Product
Global Environment Facility (UN)
Global Environmental Monitoring System (UNEP) Geographical Information System
Gross National Product
Gesellschaft für Technische Zusammenarbeit, Eschborn [German Association for Technical Cooperation]
United Nations Conference for Human Settlements (UNCHS)
International Action Programme on Water and Sustainable Agricultural Development (FAO)
International Court of Justice
International Council for Local Environmental Initiatives International Conference for Population and Development
International Crop Research Institute for the Semi-Arid Tropics (India) (CGIAR)
International Council of Scientific Unions Inter-American Development Bank
International Fund for Agricultural Development International Food Policy Research Institute
International Geosphere Biosphere Programme (ICSU)
International Human Dimension of Global Environmental Change Programme (ICSU)
International Institute for Applied Systems Analysis (Austria)
International Water and Irrigation Management Institute (Sri Lanka) (CGIAR) International Institute of Tropical Agriculture (Nigeria) (CGIAR)
International Law Association International Law Commission (UN) International Legal Materials International Labour Organisation
Intergovernmental Panel on Climate Change (WMO, UNEP) Intergovernmental Panel on Forests (CSD)
International Rice Research Institute (Philippines) (CGIAR) Carbon dioxide emission scenario (IIASA)
Kritikalitätsabschätzung [Criticality appraisal]
Kritikalitätsindex [Criticality index]
LOCALAGENDA21
Länderarbeitsgemeinschaft Wasser [Länder Working Group for Water]
Life Cycle Analysis
Lyonnaise des Eaux-Dumez (France)
Man and the Biosphere Programme (UNESCO) Max Planck Institute
North Atlantic Treaty Organization Non-Governmental Organization Organization of American States Organization of African Unity
Onchiocerciasis Control Programme (WHO)
Organisation for Economic Co-operation and Development EU
FAO FCCC FWCW GAOR GAP GATT GCM GDP GEF GEMS GIS GNP GTZ HABITAT IAP-
WASAD ICJ ICLEI ICPD ICRISAT ICSU IDB IFAD IFPRI IGBP IHDP IIASA IIMI IITA ILA ILC ILM ILO IPCC IPF IRRI IS92a KA KI LA21 LAWA LCA LED MAB-
UNESCO MPI NATO NGO OAS OAU OCP OECD XXIV
OSCE PAHO PAI PCB PEEM PIK PKK PLO POP PRA QELRO Ramsar RRA SAUR SEI SHIFT SRU T & D TRIPS UBA UN UN DTCD UN IN-
STRAW UNCED UNCHS UNCLOS UNCTAD UNDP UNEP UNESCO UNFPA UNGA UNICEF UNIDO UNPD UPOV VIP WaterGAP WBGU WEU WHG WHO WMO WRC WRI WTO WWI WZB
Organization for Security and Cooperation in Europe Pan American Health Organisation
Population Action International Polychlorinated Biphenyl
Panel of Experts on Environmental Management for Vector Control (WHO, FAO, UNEP)
Potsdam-Institut für Klimafolgenforschung [Potsdam Institute for Climate Impact Research]
Partîya Karkeren Kurdistan (Kurdische Arbeiterpartei) Palestine Liberation Organization
Persistant Organic Pollutant Participatory Rural Appraisal
Quantified Emission Limitation and Reduction Objective
Convention on Wetlands of International Importance especially as Waterfowl Habitat (signed at Ramsar, Iran)
Rapid Rural Appraisal
Societé d’Amenagement Urbain et Rural (France) Stockholm Environment Institute
Studies of Human Impact on Forests and Floodplains in the Tropics (BMFT) Rat von Sachverständigen für Umweltfragen [Council of Environmental Experts]
Towns & Development
Trade-Related Aspects of Intellectual Property Rights Umweltbundesamt, Berlin [Federal Environment Agency]
United Nations
United Nations Department of Technical Cooperation for Development United Nations International Research and Training Institute for the Advancement of Women
United Nations Conference on Environment and Development, „Rio Conference 1992“
United Nations Centre for Human Settlements (HABITAT) United Nations Convention on the Law of the Sea
United Nations Conference on Trade and Development United Nations Development Programme
United Nations Environment Programme
United Nations Educational, Scientific and Cultural Organization United Nations Population Fund
United Nations General Assembly United Nations Children’s Fund
United Nations Industrial Development Organisation United Nations Population Division
International Convention for the Protection of New Varieties of Plants Ventilated Improved Pit
Water - Global Assessment and Prognosis (Model)
Wissenschaftlicher Beirat der Bundesregierung Globale Umweltveränderungen [German Advisory Council on Global Change]
West European Union
Wasserhaushaltsgesetz [Water Management Act, Germany]
World Health Organization (UN) World Meteorological Organisation (UN) Water Resources Committee (ILA) World Resources Institute
World Trade Organisation Worldwatch Institute
Wissenschaftszentrum Berlin für Sozialforschung [Berlin Science Center]
XXV
Executive Summary A
Never have I held back the waters of the Nile, never have I barred the water its way, never have I dirtied the Nile.
PHARAONICINSCRIPTION IN THEVALLEY OFKINGS(RAMESESIII) Water resource management – the harvesting, dis- tribution, utilization, purification and control of wa- ter – has shaped the history of human civilizations to a major and permanent degree. Management of wa- ter resources is also one of the greatest challenges facing the present generation. Today, around 2 billion people have no access to clean drinking water and sanitation, and only 5% of the world’s wastewater is treated or purified. As a result, one person in two in the developing countries suffers from a water-related disease, and 5 million people die each year after drinking contaminated or infested water. Freshwater is the most important factor limiting food produc- tion, with agriculture already accounting for 70% of global water use. Worldwide, as many as 40,000 dams are in operation to secure and increase the supply of water, with a new dam being added daily. The total volume stored in reservoirs is five times that found in all the world’s rivers. International conflicts are ex- pected to arise from the growing scarcity of this cru- cial resource in many parts of the world. Referring to Ethiopia’s plans for dam projects on the Blue Nile, President Sadat, the former Egyptian president, once threatened that “Anyone who plays with the waters of the Nile is declaring war on us!”
The dimensions and implications of today’s fresh- water problems, the source of a potential major crisis of global society and the environment, have prompt- ed the Council to focus this year’s Annual Report on this burning issue. The Council analyzes and evalu- ates the total complex on the basis of facts and inter- relationships, describing in detail the available instru- ments for freshwater management and outlining ways to prevent a global crisis from unfolding. The solutions put forward by the Council are based on two elements.The first key element is generated from the Council’s “guard rail” model, which is an attempt
to resolve the dilemma between social, environmen- tal and economic goals by setting clear priorities. A robust paradigm for the “sound management of freshwater resources” is generated in the process.
The guiding principle developed by the Council can be summarized as follows: TO ACHIEVE THE GREATEST POSSIBLE EFFICIENCY WHILE OBSERVING THE IMPERATIVES OF EQUITY AND SUSTAINABILITY. This principle takes account of the fact that water, like no other environmental asset within the global commons, is both a scarceand a crucially important resource. Water is not only a commodity, but also a foodstuff. Its essential properties define the sociocul- tural and ecological framework and the non-sustain- able limits (the “guard rails”) within which water must be used efficiently in order to optimize the gen- eral welfare of humans everywhere. The very scarcity of water resources requires that, within the guard rails, there are as few obstacles as possible to an effi- cient search for beneficial freshwater use. However, efficiency can only be achieved if appropriate institu- tional, technical and educational conditions are met.
From this paradigm, the Council develops ways to solve the water crisis and addresses these to specific policy and research fields. The second key element therefore involves a global strategy for putting this paradigm into practice. The strategy is sub-divided into three components: creating an international con- sensus, instituting a World Water Charter and draw- ing up an international Plan of Action against the freshwater crisis.
Essential foundations for analyzing the global water crisis
Biological and physical foundations A description of the natural state serves as the ba- sis for further analyses. The first step is to describe the various freshwater habitats and the threats to limnetic biodiversity.This is followed by a description of the abiotic factors of key importance for the hy- drological cycle. Such a description must take ac- count of the interactions which occur between the
Summary of individual chapters 1
4 A 1 Summary
atmosphere and vegetation. In what ways can key elements of the water balance and the hydrological cycle be altered by climate change? To answer this question, the Council presents an analysis in which characteristics of the hydrological cycle under pre- sent climatic conditions are compared to those in a simulated climate with CO2doubling (equivalent to twice present-day levels). Here, the Council draws on calculations made with the ECHAM/OPYC coupled atmosphere-ocean model developed by the German Climate Computing Centre (DKRZ) and the Max Planck Institute for Meteorology (MPI). Simulations with the model show that more precipitation falls on land masses in a warmer climate, especially at high latitudes and in parts of the tropics and subtropics, while other regions have less rain. The latter include large areas of Brazil, southwest Africa, as well as Western and northern Australia. The cumulative ef- fect of human-induced climate changes will cause a forcing of the hydrological cycle, although with sub- stantial regional variances. This means that there will be losers and winners.
Water needs and water demand
The Council has predicted future trends in global water withdrawals by agriculture, industry and pri- vate households in a scenario, the basic elements of which were developed at the Potsdam Institute for Climate Impact Research and the Environmental Research Center at the University of Kassel. These computations are based on the future development of core trends relating to water, such as variations in water supply as a result of climate change, consump- tion levels in relation to demographic and economic trends, and the efficiency of water use. Water prices, cultural influences and institutional conditions for water withdrawals were not taken into consideration.
The predicted figures show that total water with- drawals by agriculture will increase by 18% in the thirty-year period between 1995 and 2025. Despite this increase, the proportion of agricultural with- drawals in relation to the total global figure falls to 56%, 19% less than in 1995. This decline is attributed to water withdrawals by industry, which will treble by the year 2025, i.e. at a rate much faster than popula- tion growth. Household water consumption will in- crease substantially, especially in Africa and Asia, but falls are expected in Europe and Latin America.
Water quality
In order to define environmental and social guard rails for water quality, it is necessary to carry out monitoring operations as comprehensively as pos- sible. However, current data on water quality are dis- tributed very unevenly in geographical terms. Hu- man impacts on water quality are impairing the nat-
ural and cultural functions of water, primarily through direct interference by agriculture and through pollutant loads emanating from point and non-point sources in settlements, the small business sector, agriculture and industry. Too little is known about the behavior of substances that enter water through human activities, about their decomposition and conversion, and about the impacts they have on ecosystems and humans. The most important factors influencing global water quality include acidification, eutrophication, salinization, and pollution caused by organic and inorganic trace compounds (pesticides and heavy metals, for example). Quality standards such as those governing agricultural and industrial uses have yet to be defined for many other types of use. Those standards already in operation tend to vary considerably from one country to the next, one example being drinking water, for which the highest quality criteria must, of course, apply. Setting limits can provide only relative safeguards against damage to health. If water stress levels are to be kept below the critical threshold, quality targets must be defined on the basis of expert knowledge and appropriate ef- forts made to meet such targets.
Floods
The greater part of the Annual Report addresses problems that arise from shortages or the poor qual- ity of water resources. However, too much water can also lead to major problems and even disasters.
Floods are the natural disasters which cause the greatest economic damage worldwide, often with great loss of human lives. The Council examines above all the mechanisms by which floods originate, how global change influences the incidence and se- verity of floods, and how the risk of floods can best be mitigated. The next Annual Report produced by the Council will focus in detail on risks and risk manage- ment.
Impacts of global change syndromes on the freshwater crisis
In its various Reports to date, the Council devel- oped a concept for the holistic analysis of global en- vironmental changes (WBGU, 1994–1996). This ap- proach enables the most important global environ- mental problems to be described in the form of 16
“clinical profiles” or syndromes afflicting the Earth System. The Council now applies this systems ap- proach to the crisis of freshwater resources. Of these 16 syndromes, the Council has selected three that are particularly relevant to water and which therefore re- quire detailed study: the Green Revolution, Aral Sea and Favela Syndromes.
5 Summary A 1
Analysis centers, firstly, on the role played by wa- ter within the “Global Network of Interrelation- ships”, a method developed by the Council for orga- nizing the complex interactions within global change into a form suitable for further analysis. By applying this method to global water problems, it is possible to examine how typical trends in the hydrosphere (such as freshwater scarcity, groundwater depletion or changes in the local water balance) are linked to oth- er trends of global change. The interactions are de- scribed and graphically portrayed as a water-cen- tered Global Network of Interrelationships.
Significance of the regional freshwater crisis
The regional importance of the freshwater crisis is emphasized further by the criticality index devel- oped by the Council. This approach involves assess- ing the water crisis using a composite indicator that combines natural water stocks and the drain on wa- ter resources caused by humans, while also taking so- ciety’s problem-solving capacity into consideration.
On the basis of detailed scenarios for water supply and water withdrawals, which were developed and computed at the level of subnational catchments by the Center for Environmental Systems Research at the University of Kassel and linked to national prob- lem-solving capacities by the Potsdam Institute for Climate Impact Research, we derive world maps that show the present “hot spots” of the freshwater crisis and other relevant aspects. With the help of addition- al scenarios for population trends, a climate scenario developed by the MPI in Hamburg, and assumptions about future water withdrawals, the regions which will face severe problems in the future are identified and presented.
The Green Revolution Syndrome
The Green Revolution Syndrome circumscribes the extensive, centrally planned and rapid modern- ization of agriculture with imported, non-adapted ag- ricultural technology, whereby negative side-effects on geographical conditions of production and the so- cial structure can occur, and indeed are put up with.
The successes of the Green Revolution are primarily achieved in irrigated agriculture; within the space of a few years, however, typical water-related problems can arise. The “evolution” of the Green Revolution Syndrome is characterized by a particular combina- tion of geopolitical, biological, population and economic trends (the interplay of national interests, the “seed revolution” in agriculture, population growth and impoverishment respectively). The Green Revolution was forced upon the people through “from above” within the framework of large- scale plans, and on a global scale through the transfer
of technology and know-how “from the rich to the poor”.
The syndrome analysis approach illustrates that the food security problem cannot be reduced to food shortage alone. Poverty is often accompanied by chronic malnutrition and famine. Close links must therefore be forged between rural development and increased production. The Council recommends in- itiating a “New Green Revolution”, i.e. enhancing food production while at the same time ensuring the growth of the small business sector, the craft trades and market practices. Secure land tenure rights are essential if farmers are to have the capacity to plan the utilization of their resources on a long-term basis.
Enhancing security of legal certainty for small farm- ers is thus a contribution to resource protection and a better means of realizing the right to food and wa- ter laid down in the International Covenant on Economic, Social and Cultural Rights. Water rights should therefore be specified in greater detail, and special institutions should be established with re- sponsibility for implementing and enforcing such rights. Environmentally sound management methods that protect resources, such as agroforestry (com- bined agriculture and forestry practices) and multi- ple cropping are very difficult to implement on a large-scale without start-up assistance. States must therefore become involved in the field of rural devel- opment and assist in the adaptation of agricultural practices. The “debt for food security swaps” recom- mended by the World Food Summit are supported by the Council as an important instrument in this re- spect.
The analysis of the Green Revolution Syndrome with special reference to water problems reveals that current irrigation systems are urgently in need of im- provement, as almost two thirds of all land irrigated worldwide is in need of rehabilitation. Subsidies should be dismantled, but without endangering the subsistence of small farmers. One way to achieve this result would be to introduce a special form of “water money” for specific target groups, whereby those most vulnerable to crisis would have to be identified.
Water resource development projects and water management systems must form an integral part of regional development programs, with preference giv- en to local, small-scale solutions.
The Aral Sea Syndrome
The Aral Sea Syndrome refers to the problems as- sociated with centrally planned, large-scale projects involving water resource development. Such projects are ambivalent – on the one hand, they provide the additional resources that are required (water for food security, renewable energy), or they protect ex- isting structures and people (flood control); on the
6 A 1 Summary
other hand, they can have severe impacts on the en- vironment and society. The effects of these large- scale installations are rarely confined to the local or regional area, but can assume far-reaching and even international proportions.
The various manifestations of the Aral Sea Syn- drome are illustrated in two case studies. Attention is directed first and foremost to the greatest environ- mental catastrophe ever caused to regional water re- sources by mankind – the desiccation of the Aral Sea that lends the syndrome its name. The second study concerns the Three Gorges Dam that China is cur- rently constructing on the Yangtze River, and de- scribes the benefits derived in the form of electrical power and flood control, as well as the serious prob- lems engendered in the form of compulsory resettle- ment of more than a million people and major envi- ronmental impacts.
How can the “susceptibility” or “vulnerability” to the Aral Sea Syndrome on the part of the various re- gions be measured? To do this, a complex global indi- cator is being developed for assessing the anthropo- genic changes in surface runoff caused by large-scale projects. A second indicator mirrors the vulnerability of the various regions to the occurrence of the syn- drome as a function of various geographical and so- cietal factors. Combining these two data sets produc- es a global indicator of the intensity of the syndrome.
Applying the syndrome approach gives rise to the general imperative to preserve the integrity and function of catchment areas and to prevent the deg- radation of ecosystems and soils. The Council atta- ches enormous weight to the reduction or avoidance of the disposition to large-scale water resource devel- opment projects with severe environmental or social consequences. If large-scale installations are never- theless essential, they must be subjected to a cautious assessment in which all environmental and social costs are first internalized. The Council specifies guard rails that may not be crossed and puts forward recommendations regarding the assessment proce- dure.
The Favela Syndrome
The Favela Syndrome refers to the progressive im- poverishment and environmental degradation brought about by uncontrolled growth of human set- tlements. Due to the sheer speed of such informal ur- banization and the failures evident in many policy fields, states become incapable of controlling further settlement (e.g. by means of development plans and building schemes) or of constructing water supply and wastewater treatment facilities. Uncontrolled ur- ban agglomerations have a very high level of water demand and in most cases an inadequate system for sewage disposal. Most people living there have no ac-
cess to clean drinking water or adequate sanitation.
This explains the diseases typical of this syndrome (e.g. cholera), which can spread to other regions of the world as a result of global mobility.
How can the Favela Syndrome be mitigated?
Firstly, it is essential to combat the basic underlying causes, such as rural exodus, which give rise to the Fa- vela Syndrome in the first place and which ultimate- ly produce the water-related problems. To eradicate the latter, the Council recommends establishing the prerequisites for integrated treatment of water-relat- ed problems in the urban agglomerations, for exam- ple by capacity-building in the local government sphere and through closer cooperation between pub- lic administration and the informal sector. Water prices are too low in most cases and lead to wastage (frequent when water supply companies are state- owned); conversely, however, water prices can often be much too high (where private-sector water traders operate) and impose a particularly heavy burden on the poor. The system for pricing water in urban ag- glomerations should therefore be changed in such a way that prices minimize wastage without, however, depriving the poor of access to water. Here, too, it may be necessary to consider paying “water money”
to the needy. The Council also recommends a series of technical measures for mitigating water crises. A very practical method could be the institution of in- ter-city partnerships focusing on solutions to the wa- ter crisis in the favelas and in the surrounding areas from which people migrate to the favelas.
Key issues in the freshwater crisis
Certain problems are common to all syndromes and are dealt with by the Council as cross-cutting
“key issues” of the freshwater crisis.
Conflicts
One such issue concerns the potential for political conflict ensuing from water resource problems. Are international “water wars” conceivable? Under what conditions are water wars especially likely? What op- tions are available for the peaceful settlement of international conflicts over water resources? These questions are examined for four conflicts with very different trajectories. Disputes over the Great Lakes in North America have generally been resolved through cooperation, and in the case of the conflict between Hungary and the Slovakia, both parties ac- cepted the jurisdiction of the International Court of Justice. There are no signs of an agreed solution to the conflict between Turkey, Syria and Iraq over the waters of the Tigris-Euphrates basin. Some observers see the possibility of a renewed escalation of political
