ARE LARGE-SCALE WATER-DIVERSION PROJECTS THE ANSWER FOR A THIRSTY WORLD?

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1 ARE LARGE-SCALE WATER-DIVERSION PROJECTS THE ANSWER FOR A THIRSTY WORLD? Earth, the water planet, contains 1.4 billion cubic kilometers of water. That amount represents 3.8 trillion liters of water for every person on Earth. Why, then, do so many experts worry about whether there will be enough water to sustain the human population? Ninety-seven percent of Earth s water is salt water. OF the remaining 3 percent that is fresh, more than 2 percent is frozen in polar ice. That means less than 1 percent of Earth s water is available to sustain life. More than 90 percent of available fresh water on Earth runs in river basins. More than 200 rivers on the planet are shared by two or more nations, and almost half of the world s human population depends on water originating in a foreign country. Although competition for water rights occurs in developed countries such as the United States, most struggles over water occur in developing countries. Rapidly growing human populations and the pressing need for industrial development often lead developing countries to undertake large-scale water projects. Many of these projects, although initially helpful, can hurt the very people they were supposed to help. BUILDING HIGH DAMS Many developing countries try to control their region s water supply by building enormous high dams. These dams, generally more than 150 meters tall, divert the normal flow of river water. High dams use moving water as a power source. They often contain hydroelectric plants that supply electricity for homes and industries. The stability of developing countries depends on the availability of electric power to rapidly growing industries and urban centers. When a river is dammed, a lake or reservoir is created behind the dam where river water backs up. This stored water can serve as a water supply for drinking and for crop irrigation. Often, industries that use large amounts of water, such as the paper industry, are important to the economies of developing countries. RELOCATING PEOPLE High dams, which are built on major rivers, form enormous reservoirs that fill hundreds of square kilometers of land. The people who live on this land are resettled while the dam is being built. The land around the dam and the areas it irrigates increase in value. As land values skyrocket in developing countries, poor farmers are often bought out by rich individuals or by corporations. These farmers must then relocate, adding more displaced poor people to the number who lost their homes prior to the dam s construction. The Manatali Dam on the Senegal River in Africa caused the relocation of about 180,000 people. Some were forced out by land investors, others by the flooding of their homeland. In India, the Narmada River Project which when completed will include 30 major dams, 125 mid-sized dams, and 3000 small dams will flood 388 square kilometers of land, forcing the resettlement of 100,000 to 1 million people. Most of these people are poor. The James Bay Project, planned for northern Quebec, Canada, would flood the ancestral lands of the 10,000 native Cree who have treaty rights to the land. If completed, this vast hydroelectric project would devastate wetland habitats for migrating and breeding birds and the fish and wildlife upon which the Cree depend. Most of the electricity the dam will produce is expected to be sold in the northeastern United States. MASSIVE DEBTS AND SALTY SOIL High-dam construction costs millions of dollars. To pay for the dams, developing countries must take out huge loans from lending institutions such as the World Bank. Many developing countries incur huge debts. Guatemala found itself deep in debt when it built the Chixoy Dam. Today, 40 percent of Guatemala s international debt payments go to pay off this loan. Guatemala s creditors, the Inter-American Development Bank and the World Bank, suggested that Guatemala fund its debt by imposing a 70% increase in the cost of electricity to its citizens. This suggestion was not received favorably by the public. Supporters of high dams argue that using reservoir water to irrigate crops will produce higher yields. The irrigation is usually beneficial to farmers in the short run. Long-term consequences of irrigation, however, can be catastrophic. Irrigation water, unlike natural rain water, may contain a good deal of dissolved salt. As the irrigation water evaporates from cropland soil, a residue of salt is left behind. Over time, the soil may become too salty to support plant life. Studies indicate that such salinization of soil has already resulted in a 24% loss of irrigated cropland worldwide. There are some irrigation systems that limit the effects of salinization, but these systems are costly and require specialized planning and management. Developing countries are so concerned with the construction of high dams for industrial development that they do no plan sufficiently for quality irrigation. Irrigation projects are often added as an

2 afterthought when the dam has been completed. By this time, the nation may be so burdened with debt, it cannot afford the necessary irrigation technology that would be less destructive to cropland. OTHER ENVIRONMENTAL EFFECTS The flooding of the land surrounding a dam may cause vegetation to rot and fish to die. The water can also become a breeding ground for disease-carrying insects that require still waters to thrive. As a result, local populations may suffer more frequently from diseases such as river blindness and guinea worm. In some ways, high dams actually increase the demand for water, not satisfy it. Industry has used about 10% of available water in most developing countries. As dams are built and hydroelectric power becomes more available, industrial water use is expected to jump 350% by the end of the century. Increased industrialization will lead to increased industrial pollution. Yet industrialization may not bring the prosperity these countries hoped for. Some multinational corporations are relocating their more polluting processing plants to developing countries. In such countries, they can use cheap water, electricity, and labor, and avoid the costs and constraints of environmental regulations in developed countries. Most of the corporations take their profits out of the host country, leaving the host country poor and environmentally damaged. WATER WARS Water is essential to life, but is available in increasingly short supply in many places in the world. Some social scientists predict that conflicts over water rights will be the cause of some wars in the future. Water conflicts are already occurring in some places, and are especially fierce in the arid Middle Eastern regions. The Nile River in Africa provides water to eight countries, which compete aggressively for it. The economies of these nations depend upon the Nile water. For example, more than 90% of Egypt is desert. Egypt relies almost entirely on the Nile for water, yet 86% of the Nile water Egypt uses originates in Ethiopia. Egypt built the Aswan High Dam in 1970 to generate electricity and irrigate more land. The silty waters of the Nile are building up behind the dam and will eventually destroy it. In the meantime, the nutrient-rich silt has been blocked form moving downstream, as it otherwise would, to the Nile delta. This once-fertile cropland is becoming barren for lack of annual deposition of Nile Silt. Egypt is planning another water project, which is likely to lead to serious conflicts with some of its neighbors. It will move more water through the Nile Basin by creating a bypass to channel Nile water away from the vast Sudd wetlands in central Sudan. The wetlands area a rich oasis for wildlife in that arid region. The planned bypass would rob the wetlands of water and deprive the people of Sudan of water as well. The lengthy civil war in Sudan was caused in part by this loss of water to parts of that nation. Turkey s recently completed Ataturk Dam diverts nearly one-third of the water that formerly flowed into Syria and Iraq. The Ataturk Dam is a part of Turkey s planned Anatolia Project, which would prevent virtually all the waters in the ancient Euphrates and Tigris rivers from flowing into Syria and Iraq. These two nations are alarmed; they cannot survive without water from these two rivers. All three nations are trying to negotiate an agreement to allocate the river water they all desperately need. REACHING AGREEMENT A way must be found to enforce equal distribution of the world s freshwater supplies. A step in that direction was taken in 1988 in San Francisco, California. At a conference on water rights sponsored by the International Rivers Network, 26 nations signed the San Francisco Declaration. Although the Declaration received widespread support, it is not binding or enforceable as international law. The document provides for the following conditions that must be met before any nation undertakes a large-scale water project: (1) free availability of information about the project; (2) respect for human rights by seeking alternatives to huge water projects that displace many people; (3) thorough longterm economic analysis prior to the project; (4) comprehensive environmental and health assessments prior to the project; (5) demonstration that public health will be improved by the project; and (6) clear information about what land is to be irrigated, how it will be irrigated, and the environmental effects of irrigation. Some countries are working together to solve their water problems. For example, rivers that flow from northern Mexico into the United States contain human and industrial wastes. The pollution is creating serious problems in Mexico and along San Diego s coast. Ecoparque, a combined park and sewage-treatment center in Tijauna, Mexico, was jointly built by groups in both countries. It treats the Tijuana River s sewage-laden water and then uses the treated water on trees and plants in Ecoparque, Mexico gets sewage treatment and a park, the United States gets a clear-flowing and nonpolluting river from Mexico.

3 Name Period Date ARE LARGE-SCALE WATER-DIVERSION PROJECTS THE ANSWER FOR A THIRSTY WORLD? REVIEW 1. Why do developing nations favor the construction of high dams? 2. Why must large numbers of people usually be relocated prior to the construction of a dam? 3. How has the diversion of reservoir water for irrigation proved to be harmful for learning? 4. What other obstacles prevent high dams from fully benefiting developing nations? DECISIONS 1. The Glen Canyon Dam has greatly reduced the flow of the mighty Colorado River. The dam provides electricity for Las Vegas and other cities. When electricity demand is high, huge quantities of water are released from the reservoir all at once. The daily water surge is ruining campsite beaches and wildlife habitats in the Grand Canyon through which the river passes. Who do you think has the greater right to control the water flow: people in the cities who need the electricity or people concerned about the Grand Canyon environment? How would you resolve this conflict? 2. Every nation has given itself the right of eminent domain, which is the ability to buy out citizens whose residences are in the way of public-works projects. For example, if your house is in the way of a projected interstate highway, the government has the right to compensate you for it and force you to vacate. Do you agree with the principle of eminent domain? What could happen if nations no longer had this right? 3. How might developing countries be discouraged from carrying out large-scale water projects that would be harmful to them in the long run? Who should be responsible for promoting alternatives in these countries?

4 GROUNDWATER DEPLETION BACKGROUND Groundwater is a vital system of underground reservoirs. These contain the world s largest supply of usable fresh water. In some areas that receive low rainfall, the withdrawal of groundwater from aquifers exceeds the rate at which rainfall can recharge the system. Only 5% of the water drawn from aquifers is the drinking and domestic uses. Almost 75% is used for irrigation worldwide the remaining 20% goes to industrial uses. In developing countries, even higher percentages are used to grow food. PART A In the space on the answer sheet, draw a diagram of the world s water cycle and label each of the following processes and components. Use arrows to show the flow of fresh water. Then answer the analysis questions on the following page. Condensation Lakes Clouds Infiltration Surface Water Animals Evaporation Oceans Sun Watershed Runoff Aquifers Glaciers/Snow Fields Precipitation Rivers Percolation Groundwater Plants PART B Incident Report #1 In California s San Gabriel Valley, an area 20 kilometers east of Los Angeles, groundwater is being pumped out of the main San Gabriel Groundwater Basin. In 1989, the situation describing the groundwater contamination in the area was presented at a congressional hearing. California takes half of its drinking water from groundwater, and agriculture uses five times that much for irrigation. Because the soil is sandy and porous, harmful pesticides were easily washed into the groundwater. At the time the pesticide use began, the hazards were not known. Also, California agriculture uses 50% of the pesticides used in the entire United States each year. The groundwater was also contaminated by industrial discharges, leaking chemical storage facilities, illegal dumping, and poorly designed landfills. Incident Report #2 In Dayton, Ohio, a fire broke out in an old paint warehouse in May of Firefighters battled the fire and quickly put it out. Unfortunately, the warehouse was built in an industrial park surrounding Dayton s field of water wells. The aquifer was only three meters below the ground in some places and the hazardous materials mixed in with the water from the fire, and the pollutants began to leak into the groundwater. As city officials tried to contain the contamination, the pollutants began to leak into the groundwater. As city officials tried to contain the contamination, they found out that abandoned sand and gravel quarries in the area had been used for dumping hazardous materials. These materials were leaking into the drinking water of nearly 1 million people. Incident Report #3 In China, 50 cities are threatened by shortages of water because groundwater is extracted faster than the systems can be recharged. The water table beneath Beijing is sinking by almost 2 meters a year and a third of its wells are suspected to be dry already. Currently, 41 large cities use groundwater polluted by nitrates from fertilizers from the extensive farmland regions. China uses more than 80% of its water for agriculture. As a result, China is chronically short of safe water, and between 1950 and 1980 they built 90,000 small dams to try to trap additional surface water. Incident Report #4 In southern India, the water table has fallen 25 meters since the early 1980s. This is due primarily to the pumping of water for agriculture in Tamil Nadu. In the northern part of the country, the number of villages short of water in the state of Uttar Pradesh has risen from 17,000 to 70,000 in the last 20 years. Of the 2,700 water supply areas provided by the government, 2,300 have dried up. India uses more than 93% of its water for agriculture to grow food for its growing population. Desalinization plants are still too expensive to lessen India s water shortages.

5 Incident Report #5 The Florida Everglades is an important marsh in southern Florida and is located south of Lake Okeechobee. To increase farming in the region, canals were cut from the lake to the Gulf of Mexico and to the Atlantic Ocean. This diverted water from Lake Okeechobee and its drainage basin has stopped the flow of water the The Everglades marsh. Lake Okeechobee recharges the Biscayne Aquifer which supplies drinking water for 4.5 million residents of Florida. In addition, much of The Everglades marsh was diked and equipped with huge drainage pumps so that sugar cane could be grown. Decomposition of the soils has resulted in the release of massive amounts of nutrients and fertilizers into the system. As a result, Everglades National Park is in danger. With the lowering of the water table, saltwater intrusion is occurring in coastal regions, killing native cypress trees. Sinkholes have developed where land has subsided. Incident Report #6 In Reno County, Kansas, the state Department of Health has been investigating the Obee Road site since July Organic chemicals had been detected at the site, including benzene, toluene, vinyl chloride, trichloroethylene, and others. The contaminants had leaded into the shallow aquifer that supplied suburban residents of Reno County. The source of the contaminants was tentatively identified as the former city of Hutchinson landfill. Until the landfill closed in 1973, this site had accepted unknown quantities of liquid waste and sludges from local industries, and solvents from the Department of Defense and local aircraft plants. Individual septic tank systems may also have contributed to the contamination because they are commonly cleaned using benzene, trichloroethylene, and dichloromethane. The Obee school system had been drawing its water from a contaminated well, but it is now receiving an alternate water supply.

6 GROUNDWATER DEPLETION PART A Draw the world s water cycle using the terms on the paper provided. ANALYSIS 1. The world s ocean is made up entirely of salt water. What is the role, if any, of the ocean in the world s fresh water cycle? 2. Describe 2 ways in which agricultural irrigation can affect the groundwater system in an area. 3. Describe 3 ways in which animals contribute to the water cycle. Are animals an essential part of the cycle? Why or why not? 4. How might global warming, caused by an increase in heat-trapping gases in the atmosphere, affect the water cycle? 5. About 113,000 billion cubic meters of precipitation fall to Earth each year. Yet the world only uses about 3,500 cubic meters of this precipitation. The rest evaporates or flows into the oceans. Why do you think people use so little of the precious resource? PART B Answer the following questions for 3 of the Incident Reports on the Groundwater Depletion Worksheet. Be sure to include the Incident Report # with your answer. 1. Where and when did the incident occur? 2. What caused the problem and what was the effect? 3. What could be, should be, or was done to help solve the problem or deal with the issue?