The Social and Environmental Effects of Large Dams,

Report to ECOROPA

Since the beginning of the historical era, man has been building dams. The ancient civilisations of Sumeria, Babylonia, Egypt, Ceylon and Cambodia, for example, were all justifiably famed for their irrigation works: indeed, the bunds and tanks which remain at such ancient capitals as Anuradhapura in Sri Lanka, or Angkor Watt in Cambodia, still survive to bear proud witness to the engineering skills of those who constructed them. Today, however, advances in concrete technology and the development of vast earth-moving machines (the largest weighing 2,000 tons) have enabled us to build dams of a size and complexity which would have staggered the ancients.

Contents

Preface;
A Ballard of Ecological Awareness Foreword by Brent Blackwelder

Part I: Introduction

Chapter One. The Overt Reasons for Building Dams

The Pace of Construction; Plans for the Future: Dam them all? Glittering Prizes: The claimed benefits of large-scale water development projects; The Lure of Hydro-Power; The Lure of Irrigation; Playing with Water: Playing with Fire?

Part II: Before the Flood

Chapter Two. Dams and Society - The Problems of Resettlement

The Scale of Resettlement Programmes; A Record of Failure; Government Insensitivity; Lack of Compensation and Inferior Land

Chapter Three. Social and Cultural Destruction

Resistance to Resettlement; Ethnic Differences Ignored; Inappropriate Housing; Housing and the Integrity of Traditional Culture; Is better Planning Possible? The Road to the Slum

Part III: After the Flood

Chapter Four. Closing the Dam: Loss of Land and Wildlife Upstream, Loss of Silt and Fertility Downstream

Loss of Agricultural Land to Flooding; Loss of Forests to Flooding; Loss of Wildlife to Flooding; The Reduction of Fertility Downstream due to Impoundment; Loss of Silt and Coastal Erosion; Conclusion

Chapter Five. Water Losses: Exceeding Gains

Introduction; Losses to Evaporation; Loss to Transpiration: The Problem of Aquatic Weeds; Losses Due to Seepage and Over-Use of Water;

Chapter Six. The Effects of Perennial Irrigation on Pest Populations

Chapter Seven. Dams and Disease

Introduction; Malaria; Schistosomiasis; Filariasis; Onchocerciasis - River Blindness; Diseases Introduced as an Indirect Result of Water Projects; Efforts to Combat Disease

Chapter Eight. The Effects of Large-Scale Water Projects on Fisheries

Short-term Successes: Long-term Failure; Dams and the Destruction of Fisheries; Pesticide Pollution and the Destruction of Fisheries; Dams, Fishing and the Net Loss of Protein

Chapter Nine. Dams, Failures and Earthquakes

Dam Failures; Earthquakes and Dams; Dams and Earthquakes: Recent Research

Chapter Ten. The Myth of Flood Control

Flood: An Increasing Menace; The Failure of a Strategy; Deforestation, Erosion and Floods; Building on the Flood Plains; Other Reasons why Structural Controls Cannot Work; The 'Trade-Off' between Flood Control, Hydropower and Irrigation; Dealing with Floods: the Ecological Approach

Chapter Eleven. Salting the Earth: The Problem of Salinisation

The Causes of Salinisation; Irrigation and Salinisation: The Intimate Connection; The Extent of the Problem; Can Salinisation and Water-Logging be Avoided?; Why No Drainage? Salinisation: The Historical Experience; Salinity and Downstream Agriculture

Chapter Twelve. Management and Maintenance - Perennial Problems

Introduction; Management and Maintenance: A Low Priority Concern; Bureaucratic Ignorance; Lack of Accountability; The Problem of Maintenance; Co-operation and Maintenance; The Conflict between Food and Cash-Crops; The Advantages of Traditional Irrigation Systems

Chapter Thirteen. Loss of Land and Food to Plantations

The Cash Crop Economy; Cash Crops and Irrigation Projects; Pushing Peasants onto Marginal Lands; Cash Crops and the Degradation of Agricultural Land; Food for What? Cash Crops and Rising Food Prices

Chapter Fourteen. The Loss of Land and Water to Industry and Urbanisation

Introduction; The Loss of Land to Urbanisation and Industrialisation in the USA; Loss of Land to Urbanisation in the United Kingdom; Loss of Land to Industrialisation and Urbanisation in Japan; The Failure to Take Land Losses into Account; The Aswan Dam and the Loss of Agricultural Land in Egypt; Loss of Water to Industrial and Domestic Uses: The United States Experience; Egypt: Water for Food or Water for Industry?

Chapter Fifteen. Dams, Pollution and the Reduction of Food Supplies

Introduction; The Export of Hazardous Industries; The Effect of Pollution on Crop Growth; Pollution and the Reduction of Fish Yields

Chapter Sixteen. Sedimentation: The Way of All Dams

Introduction; Sedimentation Rates in Temperate Areas; Sedimentation Rates in the Tropics

Chapter Seventeen. Are These Problems Inevitable?

Part IV: The Politics of Damming

Chapter Eighteen. Social and Environmental Impact Studies

Chapter Nineteen. The Politics of Damming

Politics or Oversight? The Aswan Experience; Power-Broking, Pork Barrel and Corruption; States within States

Chapter Twenty. Fudging the Books

Cost-Benefit Studies: The Record of Falsification; Over-estimating Benefits: Under-estimating Costs
Conclusion

Part V: Traditional Irrigation: Learning from the Past

Chapter Twenty-one. The Qanats of Iran

Chapter Twenty-two. The Traditional Irrigation System of the Sonjo

Chapter Twenty-three. The Traditional Irrigation System of the Chagga

Chapter Twenty-four. Traditional Irrigation in the Dry Zone of Sri Lanka

Sri Lanka's Tanks; The Importance of the Tanks; Irrigation as a Way of Life; The Sustainability of the Traditional System; Deforestation: Jeopardising the Future; Land Tenure: Traditional vs. Modern; The Growth of the State and the Breakdown of the Traditional System

Chapter Twenty-five. Traditional Irrigation in Mesopotamia

Minimising the Effects of Salinisation; The El Shabana; The Earliest Historical Experience in Mesopotamia; The Modern Experience; The Lessons of Mesopotamia

Chapter Twenty-six. The Lessons of Traditional Irrigation Agriculture; Learning to Live with Nature

Introduction; Size: A Critical Factor? Why Small is Not Enough; Seasonal vs. Perennial Irrigation; The Preservation of Forests; Balancing Water Consumption with Water Availability; Design and Management: Village Elder vs. Distant Bureaucrats; Food for Local Consumption rather than for Export; The Need for a new 'World View': The Ecological Approach

Part VI: What Should be Done?

Chapter Twenty-seven. Recommendations

Appendices

Appendix One. Reservoirs with Dams greater than 100 metres high

Appendix Two. Distribution of Saline and Alkaline Lands

The Social and Environmental Effects of Large Dams,
Edward Goldsmith and Nicholas Hildyard (1984): Wadebridge Ecological Centre, Wadebridge, Cornwall; 400p.