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One Third of
World's Population 2.7 Billion People Says New Study Groundwater Aquifers Dropping at Alarming Rates and Conflicts Over Water Predicted Washington, D.C. One third of the world's population will experience severe water scarcity within the next 25 years according to a new study by a leading global water organization. The study, which is the first to look at the complete cycle of use and reuse of the world's fresh water, finds that the water sources that supply the world's wells, lakes, and rivers are disappearing. The study was conducted by the International Water Management Institute, a research center of the Consultative Group on International Agricultural Research (CGIAR), and appears in the March issue of the International Journal of Water Resources Development, a leading refereed journal on issues of global water resources. It is being released jointly with Future Harvest, a CGIAR-sponsored organization that educates the public about the links between global peace, the environment, and agriculture. "Water scarcity is now the single greatest threat to human health, the environment, and the global food supply," said David Seckler, director general of the Water Institute and an author of the study with Randolph Barker and Upali Amarasinghe. "It also threatens global peace as countries in Asia and the Middle East seek to cope with shortages." The study, Water Scarcity in the Twenty-First Century, projects water supply and demand for 118 countries over the 19902025 period. The study examines on a country-by-country basis not only how much water is withdrawn by the four major sectors that use water‹agriculture, industry, households, and the environment‹but also how much water remains to be used and how much returns to the ground to "recharge" aquifers. In recent years, as more water has been used to support growing populations in each of these sectors, there has been less water available to recharge groundwater supplies. "Water scarcity is already a major destabilizing force within countries because different sectors of the economy are vying for scarce water resources," said Seckler. "Within the next 25 years, there is great potential for more water conflict not just within countries but between them. Historically, Egypt has threatened to go to war to protect its water supplies if necessary. And just last week, President Gaddafi of Libya warned that, 'the next Middle East war would be over dwindling water supplies.'" The study divides the countries into four categories.* The first category includes those countries that are most water scarce and in 2025 will not have enough water to maintain 1990 levels of per capita food production from irrigated agriculture and meet industry, household, and environmental needs. The countries, defined as facing "absolute water scarcity," include 17 countries in the Middle East, South Africa, and the dryer regions of western and southern India and northern China, which account for more than 1 billion people today and are projected to account for as many as 1.8 billion in 2025. The study notes that while India and China will not have major water problems on average, there will be massive regional variations in water availability. The second category includes countries that have sufficient potential water resources to meet projected 2025 requirements, but will have to more than double their efforts to extract water to do so. Twenty-four countries, mainly in Sub-Saharan Africa, are defined as extremely water scarce and include some 348 million people today and are projected to include some 894 million in 2025. Because it will be extremely difficult for these countries to find the financial resources to build enough water development projects, such as dams and irrigation systems, they are classified as having "economic water scarcity." The remaining countries of the world are in categories three and four and include North America and Europe. For these countries, there will be substantially less pressure on water supplies with moderate needs to increase water development efforts. This study notes that those who will suffer most will be the people in the world's poorest nations. Already the women and children of these countries walk great distances to retrieve water for cooking, drinking, and other household needs, farmers are losing their land as water sources decline, and wildlife is disappearing as wetlands dry up. The single greatest impact of water scarcity will be on the food supplies of the poor. To meet the world food supplies in 2025, the study provides two scenarios‹a "business as usual scenario" where no increases in irrigation efficiency are foreseen, and a scenario where irrigation efficiency is dramatically increased. Under the business-as-usual scenario, 60 percent more water will be required for irrigation to meet the world food supplies in 2025. Even if irrigation efficiency is greatly increased, between 13 and 17 percent more water will be needed and still 2.7 billion people will remain short of water. The study uses the United Nations "medium" projection for population growth. *Please note attached chart showing the countries that appear in each category. "Recent Future Harvest-sponsored research indicates that conflicts today are occurring primarily in the poor agrarian countries of the world. These are the same countries that will face severe water shortages," says Barbara Alison Rose, director of operations of Future Harvest. "Although nations have been able to manage water supplies peacefully, for the most part, this study suggests that without real action this may not be the case in the future." "Many countries, including China, India, Pakistan, Mexico and nearly all of the countries of the Middle East and North Africa, have literally been having a free ride over the past two or three decades by rapidly depleting their groundwater resources," said Seckler. "This could have catastrophic results in terms of limiting their ability to produce enough food to feed their populations." The report suggests that the main solution to the groundwater problem is to replenish groundwater aquifers, not reduce irrigation, which will reduce food production. The best way to do this is to capture more water above the ground during the wet season and allow it to percolate down into the aquifer and then pump it to provide water in the dry season. This can be accomplished through the use of percolating ponds or small reservoirs that capture rainwater. Also, pump systems around large bodies of water can inject water down into the aquifer. This is an approach being used in California. Another approach may be more effective. This is to increase rice paddy irrigation in the wet season. "The irony is that people think rice paddies waste a lot water when they are one of the best ways to maintain healthy groundwater levels," said Seckler. "The deep percolation losses of paddy irrigation recharge aquifers and replenish stream flows." The opposite problem, of rising water tables of polluted and oversalinized water, is also a severe problem in most of the arid areas of Asia and the Middle East. It is particularly acute in Pakistan. Rising water tables kill crops by waterlogging and adding a deadly level of salt to the soil. With this rising water often comes raw sewage, polluting villages and other water sources. What is required in this situation is more efficient irrigation to reduce the amount of drainage water, while simultaneously keeping salts below the root zone of plants and periodically flushing them out of the system altogether. "There is astonishing little attention to the threat of groundwater depletion in the world by engineers or policymakers," said Seckler. "The main focus is on surface water issues, but it is high time people began focusing on how to solve the water problems beneath our feet. Few seem to understand the magnitude and complexity of the groundwater problem." The Sri Lanka-based International Water Management Institute undertakes research to foster sustainable increases in the productivity of water through better management of irrigation and other water uses in river basins. ### Future Harvest builds public understanding of the role of agriculture in international issues through research and outreach on behalf of the 16 centers of the Consultative Group on International Agricultural Research (CGIAR). |
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WATER SCARCITY IN THE TWENTIETH CENTRUY
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Category 1
Afghanistan |
Category 2
Angola |
Category 3
Albania |
Category 4
Argentina |
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Definitions: Category 2: These countries face "economic water scarcity." They must more than double their efforts to extract water to meet 2025 water needs, but they will not have the financial resources available to develop these water supplies. Category 3: These countries have to increase water development between 25 and 100 percent to meet 2025 needs, but have more financial resources to do so. Category 4: These countries will have to increase water development modestly overall on average, by only five percent to keep up with 2025 demands. *These countries have severe regional water scarcity. A portion of their populations (381 million people in China in 1990 and 280 million people in India in 1990) are in Category 1. The rest of their populations are in Category 4. |
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