"The world is a much more hopeful place because of the work and life of Lester Brown. World on the Edge should be read by everyone who wants to see a better life for their children, which is just about everybody." —Ted Glick, Policy Director of the Chesapeake Climate Action Network
Chapter 2. Population Pressure: Land and Water: Water Tables Falling
Nowhere are falling water tables and the shrinkage of irrigated agriculture more dramatic than in Saudi Arabia, a country as water-poor as it is oil-rich. After the Arab oil export embargo in the 1970s, the Saudis realized they were vulnerable to a counter embargo on grain. To become self-sufficient in wheat, they developed a heavily subsidized irrigated agriculture based largely on pumping water from a deep fossil aquifer. 34
After being self-sufficient in wheat for over 20 years, in early 2008 the Saudis announced that, with their aquifer largely depleted, they would reduce their wheat planting by one eighth each year until 2016, when production will end. By then Saudi Arabia will be importing roughly 15 million tons of wheat, rice, corn, and barley for its population of 30 million. It is the first country to publicly project how aquifer depletion will shrink its grain harvest. 35
The Saudis are not alone. Scores of countries are overpumping aquifers as they struggle to satisfy their growing water needs. Most aquifers are replenishable but some are not. For example, when aquifers in India and the shallow aquifer under the North China Plain are depleted, the maximum rate of pumping will be automatically reduced to the rate of recharge.
But for fossil aquifers, like the Saudi aquifer, the vast Ogallala aquifer under the U.S. Great Plains, or the deep aquifer under the North China Plain, depletion brings pumping to an end. Farmers who lose their irrigation water have the option of returning to lower-yield dryland farming if rainfall permits. But in more arid regions, such as in the southwestern United States and parts of the Middle East, the loss of irrigation water means the end of agriculture. 36
In Yemen, a nation of 23 million people neighboring Saudi Arabia, the water table is falling by roughly 6 feet a year as water use outstrips aquifer recharge. With one of the world’s fastest-growing populations and with water tables falling everywhere, Yemen is quickly becoming a hydrological basket case. Grain production has fallen by half over the last 35 years. By 2015, irrigated fields will be a rarity and the country will be importing virtually all of its grain. Living on borrowed water and borrowed time, Yemen ranks high on the list of failing states. 37
Falling water tables are already adversely affecting harvests in some larger countries, including China, which rivals the United States as the world’s largest grain producer. A groundwater survey released in Beijing in August 2001 revealed that the water table under the North China Plain, an area that produces over half of the country’s wheat and a third of its corn, was falling fast. Overpumping has largely depleted the shallow aquifer, forcing well drillers to turn to the region’s deep aquifer, which is not replenishable. 38
The survey reported that under Hebei Province in the heart of the North China Plain, the average level of the deep aquifer was dropping nearly 3 meters (10 feet) per year. Around some cities in the province, it was falling twice as fast. He Qingcheng, head of the groundwater monitoring team, notes that as the deep aquifer is depleted, the region is losing its last water reserve—its only safety cushion. 39
A World Bank study indicates that China is mining underground water in three adjacent river basins in the north—those of the Hai, which flows through Beijing and Tianjin; the Yellow; and the Huai, the southern most of the three. Since it takes 1,000 tons of water to produce 1 ton of grain, the shortfall in the Hai basin of nearly 40 billion tons of water per year (1 ton equals 1 cubic meter) means that when the aquifer is depleted, the grain harvest will drop by 40 million tons and China will lose the food supply for 130 million of its people. 40
As serious as water shortages are in China, they are even more serious in India, where the margin between food consumption and survival is so precarious. To date, India’s 100 million farmers have drilled more than 21 million wells, investing some $12 billion in wells and pumps. In August 2004 Fred Pearce reported in New Scientist that “half of India’s traditional hand-dug wells and millions of shallower tube wells have already dried up, bringing a spate of suicides among those who rely on them. Electricity blackouts are reaching epidemic proportions in states where half of the electricity is used to pump water from depths of up to a kilometer.” 41
As water tables fall, well drillers are using modified oil-drilling technology to reach water, going down a half mile or more in some locations. In communities where underground water sources have dried up entirely, all agriculture is now rain-fed and drinking water must be trucked in. Tushaar Shah, who heads the International Water Management Institute’s groundwater station in Gujarat, says of India’s water situation, “When the balloon bursts, untold anarchy will be the lot of rural India.” 42
Growth in India’s grain harvest, squeezed both by water scarcity and the loss of cropland to non-farm uses, has slowed since 2000. A 2005 World Bank study reports that 15 percent of India’s food supply is produced by mining groundwater. Stated otherwise, 175 million Indians are fed with grain produced by water mining. 43
In the United States, the USDA reports that in parts of Texas, Oklahoma, and Kansas—three leading grain-producing states—the underground water table has dropped by more than 30 meters (100 feet). As a result, wells have gone dry on thousands of farms in the southern Great Plains, forcing farmers to return to lower-yielding dryland farming. Although the depletion of underground water is taking a toll on U.S. grain production, irrigated land accounts for only one fifth of the U.S. grain harvest, compared with close to three fifths of the harvest in India and four fifths in China. 44
Pakistan, a country with 177 million people that is growing by 4 million per year, is also mining its underground water. In the Pakistani part of the fertile Punjab plain, the drop in water tables appears to be similar to that in India. Observation wells near the twin cities of Islamabad and Rawalpindi show a fall in the water table between 1982 and 2000 that ranges from 1 to nearly 2 meters a year. 45
In the province of Balochistan, which borders Afghanistan, water tables around the capital, Quetta, are falling by 3.5 meters per year—pointing to the day when the city will run out of water. Sardar Riaz A. Khan, former director of Pakistan’s Arid Zone Research Institute in Quetta, reports that six of Balochistan’s basins have exhausted their groundwater supplies, leaving their irrigated lands barren. 46
Iran is overpumping its aquifers by an average of 5 billion tons of water per year, the water equivalent of one fourth of its annual grain harvest. It too faces a day of reckoning. 47
Israel, even though it is a pioneer in raising irrigation water productivity, is depleting both of its principal aquifers—the coastal aquifer and the mountain aquifer that it shares with Palestinians. In response, Israel has banned the irrigation of wheat, its staple food, and is now importing nearly all the wheat it consumes. Conflicts between Israelis and Palestinians over the allocation of water are ongoing. 48
In Mexico—home to a population of 109 million that is projected to reach 129 million by 2050—the demand for water is outstripping supply. Mexico City’s water problems are well known. Rural areas are also suffering. In the agricultural state of Guanajuato, the water table is falling by 2 meters or more a year. In the northwestern state of Sonora, farmers once pumped water from the Hermosillo aquifer at a depth of 10 meters (35 feet). Today they pump from more than 120 meters. At the national level, 51 percent of all water extraction is from aquifers that are being overpumped. 49
Since the overpumping of aquifers is occurring in many countries more or less simultaneously, the depletion of aquifers and the resulting harvest cutbacks could come at roughly the same time. And the accelerating depletion of aquifers means this day may come soon, creating potentially unmanageable food scarcity.
34. Craig S. Smith, “Saudis Worry as They Waste Their Scarce Water,” New York Times, 26 January 2003.
35. Andrew England, “Saudis to Phase Out Wheat Production,” Financial Times, 10 April 2008; USDA, op. cit. note 2; U.N. Population Division, op. cit. note 8.
36. Michael Ma, “Northern Cities Sinking as Water Table Falls,” South China Morning Post, 11 August 2001; Smith, op. cit. note 34; John Opie, Ogallala: Water for a Dry Land, 2nd ed. (Lincoln, NB: University of Nebraska Press, 2000), p. 3.
37. U.N. Population Division, op. cit. note 8; USDA, op. cit. note 2; Christopher Ward, “Yemen’s Water Crisis,” based on a lecture to the British Yemeni Society in September 2000, July 2001; Fund for Peace and Foreign Policy, “The Failed States Index,” Foreign Policy, July/August 2009, pp. 80–93.
38. Ma, op. cit. note 36; share of China’s grain harvest from the North China Plain based on Hong Yang and Alexander Zehnder, “China’s Regional Water Scarcity and Implications for Grain Supply and Trade,” Environment and Planning A, vol. 33 (2001), and on National Bureau of Statistics of China, China Statistical Yearbook 2008, electronic database, at www.stats.gov.cn/tjsj/ndsj/2008/indexeh.htm, viewed 9 June 2009.
39. Ma, op. cit. note 36.
40. World Bank, China: Agenda for Water Sector Strategy for North China (Washington, DC: April 2001), pp. vii, xi; U.N. Population Division, op. cit. note 8; USDA, op. cit. note 2.
41. Number of farmers and well investment from Peter H. Gleick et al., The World’s Water 2006–2007 (Washington, DC: Island Press, 2006), p. 148; number of wells and rate of aquifer depletion from Fred Pearce, “Asian Farmers Sucking the Continent Dry,” New Scientist, 28 August 2004.
42. Pearce, op. cit. note 41.
43. USDA, op. cit. note 2; John Briscoe, India’s Water Economy: Bracing for a Turbulent Future (New Delhi: World Bank, 2005); U.N. Population Division, op. cit. note 8.
44. USDA, Agricultural Resources and Environmental Indicators 2000 (Washington, DC: February 2000), Chapter 2.1, p. 6; irrigated share calculated from FAO, op. cit. note 3; harvest from USDA, op. cit. note 2; Sandra Postel, Pillar of Sand (New York: W. W. Norton & Company, 1999), p. 77.
45. U.N. Population Division, op. cit. note 8; fall in water table from “Pakistan: Focus on Water Crisis,” U.N. Integrated Regional Information Networks News, 17 May 2002.
46. “Pakistan: Focus on Water Crisis,” op. cit. note 45; Sardar Riaz A. Khan, “Declining Land Resource Base,” Dawn (Pakistan), 27 September 2004.
47. Chenaran Agricultural Center, Ministry of Agriculture, according to Hamid Taravati, publisher, Iran, e-mail to author, 25 June 2002; USDA, op. cit. note 2.
48. Deborah Camiel, “Israel, Palestinian Water Resources Down the Drain,” Reuters, 12 July 2000; USDA, op. cit. note 2; “Palestinian Water Crisis Deepens,” BBC News, 20 April 2009.
49. U.N. Population Division, op. cit. note 8; Tushaar Shah et al., The Global Groundwater Situation: Overview of Opportunities and Challenges (Colombo, Sri Lanka: International Water Management Institute, 2000); Karin Kemper, “Groundwater Management in Mexico: Legal and Institutional Issues,” in Salman M. A. Salman, ed., Groundwater: Legal and Policy Perspectives, Proceedings of a World Bank Seminar (Washington, DC: World Bank, 1999), p. 117; U.N. Development Programme, Human Development Report 2006 (Gordonsville, VA: Palgrave Macmillan, 2006), p. 146.
Copyright © 2009 Earth Policy Institute