About the Author xi Preface xiii Acknowledgements xv Introduction 1 References 5 1 Our History with Water: What Can Be Learned from Past Water-based Communities 7 Mesopotamia 8 Qanats 11 Egypt 12 Ancient Greece 14 Classical Greece and Roman 16 Roman Empire 16 Ancient American Civilisations 20 Some of the Changes from the Thirteenth to Nineteenth Centuries 23 What Can We Learn from These Ancient Approaches to Water Management? 25 References 27 2 Water Movement in Time and Space 31 Atmospheric Water, Clouds and Precipitation 36 Spatial Variations in Precipitation and Run-off 37 Groundwater 42 Water Movement Through Evaporation and Precipitation 44 Glaciers, Ice Fields and Snow Melt 45 Groundwater 47 Rivers, Lakes and Reservoirs 50 Rivers 50 Lakes 52 Lakes and Reservoirs 57 References 59 3 Human Needs and Water Demands. How Much Water Do We Need? 63 Our Basic Water Needs 64 Our Right to Water 65 Basic Water Requirements 69 Factors Driving Water Demand 70 Water Withdrawals and Use in the United States 71 Sectoral Water Demand and Consumption 77 Agriculture 77 Energy 80 Industry 82 Humans and Human Settlements 82 Water Abstractions and Use in Europe 86 References 88 4 Water Resources 93 The Driving Forces Behind the Global Climate 99 Evaporation and Precipitation 102 Glacier and Snowmelt 103 Groundwater 105 Surface Freshwater Resources 111 Lakes and Reservoirs 115 Sand Dams 117 Rainwater and Fog Harvesting 119 Rainwater Harvesting for Domestic Use 124 Rainwater Quality 124 Floods and Droughts 125 Floods 125 Droughts 129 References 131 5 Water Scarcity 135 What Is Water Scarcity? 136 Our Right to Water 137 Water Availability, Demand and Allocation 138 Industry Demands 141 Municipal Water Demands 141 Water Demands for Agriculture 141 Estimating Freshwater Availability and Scarcity Using Indices 142 Falkenmark Index 144 Water Poverty Index (WPI) 145 Access 146 Water Quality and Availability 146 Water for Agriculture and Other Productive Activities 146 Capacity to Manage Water 147 Environmental Aspects 147 Questions of Spatial Scale 147 The Social Water Stress Index 152 Water Resources Vulnerability Index (WRVI) 153 Water Resources Availability and Food (Especially Cereals Imports) 154 Index of Local Relative Water Use and Reuse 154 Watershed Sustainability Index and Water Resources Vulnerability Index 156 Environmental Sustainability Index (ESI) 157 References 164 6 Water Quality: Some Management and Use Issues 169 Added Nutrients and Eutrophication 174 Phosphorus 181 Controlling Nutrient Inputs 182 Nitrogen 183 Eutrophication and Harmful Algal Blooms 191 Mitigation of Nitrogen and Phosphorus Inputs to the Environment 193 Artificial Mixing 198 Dredging 200 Algicides 200 Examples of European and United States Regulations and Regulatory Authorities Responsible for Water 202 Local Water Agencies 209 Municipal Water Departments 209 Water and Sewer Districts 209 Flood-control Districts 209 Mutual Ditch and Irrigation Companies 209 Regional Water Agencies 210 Conservancy Districts 210 Natural Resource Districts 210 Groundwater Management Districts as in Kansas 210 State Water Agencies 210 Multistate Water Agencies 211 Missouri River Basin Association 211 The Ogallala Aquifer 212 References 215 7 Drinking Water Treatment 221 Aims for Provision of Drinking Water and Sanitation 222 Drinking Water Treatment 233 Pre-treatment 241 Screens 241 Filtration 247 Sand Pre-filters 248 Activated Carbon 251 Ion Exchange 252 Membrane Filters 253 Microfiltration 256 Ultrafiltration 257 Nanofiltration 257 Reverse Osmosis 258 Membrane Integrity 258 Backwashing 258 Coagulation and Flocculation 259 Dissolved Air Flotation (DAF) 261 Slow Sand Filtration 266 Chemical and Microbiological Actions 269 Natural Organic Matter 270 Arsenic removal 274 Cleaning a Slow Sand Filter 276 Disinfection 277 Ultraviolet Radiation 277 Ozone 279 Chlorine 281 Disinfection By-products of Chlorination 283 Sodium Hypochlorite and Calcium Hypochlorite Disinfectants 283 General Considerations for Disinfection 284 References 285 8 Wastewater Treatment 291 Preliminary Treatment: Screening and Grit Removal 296 Storm Water 298 Primary Sedimentation 298 Activated Sludge (AS) Process 299 Diffused Air 299 Surface Aeration 301 Vertical Shaft Rotors 301 Horizontal Shaft Aerators 302 Mixed Liquor Suspended Solids 304 Biological Filtration 304 Possible Problems with Filters 308 Humus Tanks (Secondary Sedimentation Tanks) 309 Rotating Biological Contactors (RBC) 310 Sludge Treatment and Disposal 311 Waste Stabilisation Pond Treatment 312 Anaerobic Ponds 314 Facultative Ponds 314 Maturation Ponds 315 Water Storage and Treatment Reservoirs 315 Constructed Wetlands (CWs) 316 Vertical Flow Wetlands 318 Septic Tanks 321 Disposal of Sewage Sludge 322 Incineration 322 Disposal to Land 323 Disposal to Agriculture 324 References 327 9 Climate Change and Its Implications for Freshwater in the Future 331 Impacts on Human Settlements 338 Precipitation 340 Streamflow 342 Groundwater 344 Changes in Water Quality 344 Droughts 345 Climate Change and Freshwater and Terrestrial Ecosystems 348 Inland Fisheries 350 Effects on Agriculture and Food 352 References 354 10 Sustainability: The Way Ahead and Can We Achieve It - A Summary 361 Virtual Water and Water Footprint 365 Reducing Water Demand 367 Domestic Water Saving Strategies 370 References 373 Glossary 377 Index 383.