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State of the World 2004

Boosting Water Productivity. Sandra Postel and Amy Vickers. State of the World 2004. Boosting Water Productivity. Overview:. A New Mindset for Managing Water Water-Rich, Water-Poor Water, Crops, and Diets Cities and Homes Industrial Water Use and Material Goods Consumption

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State of the World 2004

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  1. Boosting Water Productivity Sandra Postel and Amy Vickers State of the World 2004

  2. Boosting Water Productivity Overview: • A New Mindset for Managing Water • Water-Rich, Water-Poor • Water, Crops, and Diets • Cities and Homes • Industrial Water Use and Material Goods Consumption • Policy Priorities

  3. Freshwater Ecosystems • Rivers, lakes, wetlands, and underground aquifers • They store, move, and cleanse water as it cycles between sea, air, and land • Healthy ecosystems need • - Minimum quality and quantity of water • - Natural flow pattern

  4. World Water Use Industry (22%) Agriculture (70%) Towns and Municipalities (8%) Source: World Bank, World Development Indicators, 2001

  5. Human Influences on Freshwater Ecosystems • Water tables are falling from overpumping of groundwater • Many streams and rivers run dry for portions of the year • Large inland lakes are shrinking • World’s freshwater wetlands have diminished in area by half

  6. Current Water Use Patterns Are Unsustainable • Impacts accelerate with increases in population and consumption • Large-scale water development projects (i.e., dams, reservoirs, diversion projects) have social and ecological costs: • - Ecosystems destroyed • - Fisheries decimated • - Aquatic species imperiled • - People displaced from • their homes

  7. 1. A New Mindset for Managing Water • Freshwater is a life support system for ecosystems • Must allocate sufficient water throughout the year to protect valuable ecosystem functions • Can use remaining water to satisfy human demands efficiently, equitably, and productively

  8. 2.8 Egypt 3.6 India 8.5 China 12.3 Russian Federation 18.0 United States 20.3 Brazil 21.3 Australia 40.2 Germany GDP per cubic meter of water use (2000 dollars) Source: FAO, USGS, OECD Water Productivity of Selected Countries Water Productivity: Value of economic goods and services per cubic meter of water extracted from the natural environment

  9. Water-poor areas have higher demands because crop production requires more irrigation in drier climates 2. Water-Rich, Water-Poor • Uneven distribution of water on a global scale • - 6 countries (Brazil, Russia, Canada, Indonesia, China, and Colombia) account for half of Earth’s freshwater supply

  10. Ethiopia 42 348 Brazil 527 Russian Federation 640 India 1011 Egypt 1932 United States Estimated Annual Water Withdrawals Per Capita, Selected Countries (2000) Cubic Meters Per Person Per Year Source: FAO, USGS

  11. Ethiopia: 84% of the Nile’s flow originates within its territory, but faces famine due to drought Phoenix, Arizona: Desert climate, but imports water from Colorado River Affluence and Poverty • Influence of power, politics, and money can override natural abundance or scarcity of water

  12. Populations Lacking Access to Safe Drinking Water and Sanitation (2000) No Safe Drinking Water No Adequate Sanitation Region Africa 36% 40% Asia 19% 53% Latin America & Caribbean 13% 22% Source: World Health Organization 1 out of 5 people in developing world (1.1 billion people) face risk of disease and death due to lack of access to safe drinking water

  13. Meeting Basic Needs • Urgent task: to provide all people with minimum amount of clean water needed for good health and sanitation • More than enough water to accommodate everyone’s basic needs but political will and financial commitment lacking • When private corporations manage water systems, cost-recovery can take priority over meeting basic needs

  14. 3. Water, Crops, and Diets Must raise productivity of agricultural water use to meet growing food needs as water stress deepens and spreads • Three Challenges: • Delivering and applying water to crops more efficiently • Increasing yields per liter of water consumed • Shifting diets to satisfy nutritional needs with less water

  15. Water, Crops, and Diets • Surface water irrigation efficiency is typically poor (can be as low as 25-40%) • Losses due to leaks, seepage, evaporation

  16. Micro-irrigation methods • drip and micro-sprinklers reduce volume of water applied to fields by 30-70% and increase crop yields by 20-90% Changes in cropping patterns and growing methods • using high-yielding and early- maturing crop varieties • deficit irrigation: only watering plants during critical growth stages Improving Irrigation Efficiency

  17. Affordable technologies for small plots • ex.: treadle pumps: human powered devices that give access to shallow groundwater Collecting and storing rainfall • using ponds, check dams, and other structures to irrigate crops during dry season, recharge groundwater Improving Irrigation Efficiency

  18. 4902 Water consumed to supply 10g of protein Water consumed to supply 500 calories 251 1000 204 rice beef Dietary Choices 4902 Liters of Water 1515 421 251 1000 219 89 303 67 132 135 204 potatoes beans wheat rice poultry beef Based on California crop yields and water productivity. Source: Renault and Wallender (2000)

  19. Cutting consumption of animal products in half would reduce: • - nation’s dietary requirements of water by 37% • - incidence of heart disease • - cruelty to animals • - pollution of streams fromindustrial animal feedlots Dietary Choices • Average U.S. diet, high in meat content, requires twice as much water as an equally nutritious vegetarian diet

  20. 4. Cities and Homes • Waste is a major urban water management problem • In many cities, water losses are 15% - 40%, some higher • Unaccounted-for Water (UFW): volume of water withdrawn from nature but that never reaches an end-user, due to • - Leaky pipes and mains • - Theft • - Meter inaccuracies

  21. - Rivers run dry • Habitats wither • Wildlife disappears Problems with Urban Water Losses • Surrounding regions experience water stress: withdrawals outstripping available supplies • When surplus water is extracted • More energy required to pump, treat, and distribute excess water • This “lost” water, if recovered, could help cities facing scarcity meet their water needs

  22. Household Water Use, Selected Cities and Countries 47 149 218 255 281 832 Liters Per Capita Per Day Source: Thompson et al. (2001), National Water Demand Management Centre, Environment Agency, U.K. (2003), Gombos (2003), Water Services Association of Australia (2001), Mayer et al. (1999)

  23. Install water-efficient fixtures • (toilets, showerheads, faucets) • Choose water-efficient appliances • (clothes washers, dishwashers) Household Water Use Tips to reduce indoor household water consumption by almost 50%:

  24. Household Water Use • Large domestic water demand for irrigation of lawns, landscapes, and golf courses • - 30 billion liters of water a day in the U.S. • 45 million kg of fertilizers and chemicals used per year • Excess fertilizers and chemicals run off into streams, seep into groundwater • - contaminating drinking water • - polluting lakes and ponds

  25. Choose natural landscaping and native plants • - drought-adaptive grasses, groundcovers, wildflowers and plants that thrive naturally in local climate Household Water Use To reduce outdoor water consumption… • Use more efficient sprinklers and irrigation systems

  26. 5. Industrial Water Use and Material Goods Consumption • Major water-using industries: • Thermal electric power • Iron and steel • Pulp and paper • Chemicals • Petroleum • Machinery manufacture • Water is used for cooling, washing, processing, heating • In developing countries, pollutant loads rising along with industrial water demand

  27. Industrial Water Use and Material Goods Consumption • Incentives for increasing efficiency of water use in industrial facilities: • Cost savings • Need to comply with permit requirements • Advances in technologies that allow process water to be reused and recycled • Availability of low-cost reclaimed nonpotable water

  28. How Individuals Can Reduce Their Impacts on Freshwater • Purchase fewer material goods • Eat a nutritious, less meat-intensive diet • Select native plants and grasses for landscapes, rely on natural rainfall

  29. How Individuals Can Reduce Their Impacts on Freshwater • Install water-efficient appliances and fixtures • Support local land use ordinances that protect wetlands, aquifers, and watersheds • Serve on local water management boards to monitor and enforce water protection strategies

  30. 6. Policy Priorities: Government Action • Protect public trust in water • Institute or strengthen groundwater regulations to promote sustainable use • Implement tiered water pricing to encourage conservation: unit price of water increases along with consumption

  31. Policy Priorities: Government Action • Restrict water use during seasonal lows • Encourage water trading between willing sellers and buyers to reallocate available supply

  32. About the Authors “Boosting Water Productivity” by Sandra Postel and Amy Vickers Sandra Postel is co-author of Rivers for Life: Managing Water for People and Nature (Island Press, 2003), and director of the Global Water Policy Project in Amherst, MA. More at www.globalwaterpolicy.org Amy Vickers, author of the award-winning Handbook of Water Use and Conservation: Homes, Businesses, Landscapes, Industries, Farms (WaterPlow Press) is an engineer and water conservation specialist based in Amherst, MA. More at www.waterplowpress.com

  33. More information on State of the World 2004 at www.worldwatch.org

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