In many lands water scarcity poses a threat to both health and wealth. Hydrologists designate water stressed countries as those with annual supplies of 1,000 - 2,000 m3/person. When the figure drops below 1,000 m3, nations are considered water scarce. Chronic water shortages affect 40% of the world's population, spread across 80 nations; current estimates show the demand for water increasing at 2.3% annually, or doubling every 21 years, thus deepening the need. Water shortages are worst in poor countries: 26 countries today fall into the water scarce category and face severe constraints on food production, economic development, and human and environmental welfare from a lack of usable fresh water. The conservation of water and the regulation of rivers for irrigation and generation of hydroelectric power are matters of great social and economic importance in the world today, particularly in arid countries. International River Basins "An international river is one whose water course traverses, or whose catchment basin lies in, the territories of two or more sovereign states." More than 200 separate river basins in the world are shared by two or more countries. These international rivers constitute a significant portion of the world's freshwater resources and are great assets to the nations that share them. Since a basin is interconnected through the flow of a river's waters, the use of waters in one part of the basin may affect the use in another part. Incentives for cooperative management do not exist when an upstream country uses an international river to the detriment of a downstream country that has no reciprocal power over the upstream country: the management of water is further complicated by the tendency to treat water as a commodity rather than as a finite natural resource. Consequently, shared river resources often suffer greater environmental abuse and are not as productively used as comparable national water resources. The uneven distribution of positive and negative physical impacts stemming from differing demands among the basin countries for water resources frustrate cooperative action to manage and develop the river for mutual benefit. East Africa, specifically the Nile River region, is an area that exemplifies these concepts. The Nile River Basin In East Africa and the Middle East freshwater is scarce and widely shared by countries with enormous economic, military, and political differences; over-exploitation, depletion, and deterioration of freshwater in rivers, lakes, and groundwater aquifers are prevalent problems. Most of the known conventional water resources have already been developed or will soon be fully exploited in most of the region's countries and, by the end of this century, six Nile riparians will exceed the hydrologic measure of water scarcity. The water resources in this arid area are unevenly distributed and used, and every major river in the region crosses international borders, thus making the potential for conflict over water great. (See Maps 1 and 2 in appendix.) Figure 2. Nile River Watershed Area by State.
The Nile River Basin, along with all the water it carries, traverses the territories of nine separate nations: Burundi, Egypt, Ethiopia, Kenya, Rwanda, the Sudan, Tanzania, Uganda, and Zaire. (See Figure 2.) Although these countries share one of the greatest rivers in the world, many inequities over this common resource exist and are especially difficult to redress. The Nile presents a classic riparian problem: a river does not recognize boundaries between states - it flows continuously. The water flowing from the source is the same water that leaves the mouth of the river and enters the ocean. (See Figure 3.) The ways in which it is diverted, collected, used, and returned to the stream determines the quality and quantity of water each successive downstream nation will receive. Conflicts over Nile River water provide examples of unresolved international water issues in a shared basin. Project Focus Water is pervasive in all biological and physical systems, and its use is inextricably intertwined with many of society's efforts to enhance economic and social well-being. Water is a substance of paramount ecological, economic and social importance. Interrelationships inherent in water use should encourage integrated basinwide management strategies. Nile basin countries, instead of opposing each other, could direct their attentions toward multinational agreements and policies, defining collective basinwide management strategies. Developing the Nile's water resources for common benefit will require a cooperative approach treating the Nile Basin as one hydrologic unit and all riparian states as equal stakeholding partners. Figure 3. The Nile River.
Issues In an International River Basin The Nile region boasts a unique situation with regard to economics and development. The pattern of water demand and use in the Nile basin contrasts sharply with the pattern of supply: the upper valley states, in particular Ethiopia, are best placed geographically, but the lower valley states, especially Egypt, have the vital resource interest and can exercise decisive military and economic power. The paradox is that the countries contributing the most water are using the least, but the countries using the most are those that have the power. The utilization level of Nile waters by the co-basin states varies with their respective socio-economic development: Egypt, the most developed nation in the basin, uses 55.5 km3 of water each year and projects demands of 65.5 km3. The Sudan, the most rapidly developing basin nation, consumes about 13 km3 per year with a projected use of 30 km3 expected as agricultural irrigation expands. Egypt and the Sudan account for over 90% of the water drawn from the Nile. However, there are seven other basin states and their demand for water will inevitably grow. (See Figure 4.) The upper riparian states, Tanzania, Uganda, Rwanda, Kenya, Burundi, and Zaire, utilize 0.05 km3 collectively; Ethiopia utilizes only 0.6 km3. This is ironic because combined, these states contribute 72 km3 of water per year, or about 86 percent of the Nile's flow. Figure 4. Water Situations for Selected Nile Basin States.
Political boundaries present real obstacles to efficient water use and are often more difficult to overcome than physical ones. Much of the strain surrounding water in the Nile basin stems from a zero-sum game perception: one nation's gain is another nation's loss. As long as nations remain locked in such thinking, the tension and distrust among them will persist. A country faced with the prospect for a cooperative endeavor has three broad options: (1) to seek international agreement with neighboring states for joint management or development; (2) to develop a national plan that will maximize the country's net benefits from the same resources irrespective of other basin countries' actions; or (3) to retain the status quo and do nothing. The determination of the most favorable option is based upon the assumption that for each party the net benefits desired from international agreement must be greater than those associated with the national option, which in turn must be greater than the status quo alternative. All nine basin states could equitably share, utilize, and manage natural resources to the benefit and welfare of the basin's population, but optimum development will require treating the drainage basin as a unit and breaking through the barriers. "The tendency of political analysts has been to make alarmist predictions based on extrapolations of competing demands for water in the face of dwindling supplies while ignoring the great potential for managing and moderating those demands internally." The task calls for a fundamental change in perception and attitude. Water must be recognized as a valuable and vulnerable resource. It must no longer be taken for granted as an inexhaustible free good: this leads to perceptions of water scarcity. Scarcity is, to some extent, a relative concept. The Nile states, although not water rich, do have a fairly substantial freshwater resource available for their use. Unfortunately, the pattern of water allocation, along with policies that discourage (or at least do not encourage) efficient utilization lead to a perception that water is more scarce than in actuality. Nile water is currently mismanaged and heavily misused which exacerbates regional water problems. Management, therefore, must be addressed by all the basin states to maximize available water resources, since options for developing new supplies are severely limited. A management model has to be a combination of efficient allocation principles for locally competing demands and rules for fair regional sharing between up and downstream users. Integrated water management can be contemplated on at least three levels: basinwide, regional, and local. Great opportunities exist for better use of water before it is eventually lost through discharge to the sea or evaporation: most involve improved management practices at all levels. The Nile is a geographical unit -- projects for its full development must also form a unity, the parts of which must work together. Before discussing the shared problems and management opportunities available to the parties involved, it is important to understand the region's hydrology, or where the Nile water comes from in the first place. Nile River Hydrology The Nile is one of the great natural wonders of the world: it is the longest river, flowing south to north 6,825 kilometers (km) over 35 degrees of latitude. The Nile's catchment basin covers approximately one-tenth of the African continent, with an area of 3,007,000 square kilometers. (km2) (See Map 3 in appendix.) The Nile basin, because of its size and variety of climates and topographies, constitutes one of the most complex of all major river basins. For the vastness of the Nile basin, however, the river's annual discharge is relatively small. The annual flow of the Nile is about 84 billion cubic meters (bcm). The Nile is distinguished from other great rivers of the world since half of its course flows through country with no effective rainfall. Throughout the northern reaches of the Nile human civilizations have been dependent upon the river for their very survival: without the river, Egyptian civilization would not exist. (See Maps 4 and 5 in appendix.) The Nile has two major tributaries, the White Nile and the Blue Nile. These two principal headwaters are very different from each other: they arise in contrasting climatic and physiographical areas and are characterized by disparate hydrological regimes. (See Figure 5.) The White Nile flows out of the tropical rainbelt of Central Africa with relatively little interseasonal variation. Its principal source is Lake Victoria, the second largest freshwater lake in the world after Lake Superior. Nearly one-third of Victoria's entire inflow is derived from the 60,000 km2 Kagera River catchment. Most of Rwanda and Burundi lie in this basin, while 33 percent and 10 percent of the catchment area fall within Tanzania and Uganda, respectively. Lake Victoria straddles the equator and lies 5,611 km from the mouth of the river. Figure 5. Cross Sections of the Two Major Nile Tributaries from their Sources to the Mediterranean Sea.
From this lake issues the Victoria Nile, which passes through Lakes Kyoga and Albert. From Lake Albert to Nimule on the Uganda-Sudan border, the river is known as the Albert Nile. After plunging through the Fola rapids and into the Sudan, the river becomes the Behr el-Jebel (meaning mountain sea) and travels over a 168 km distance to reach Juba, the capital of southern Sudan. At this point the river has 4,787 km to travel before reaching the Mediterranean Sea. A great deal of the Behr el-Jebel's waters, however, never reach the sea. North of Juba the river reaches the bottom of its upstream drainage basin. Its slope flattens dramatically: water spills out over its banks and spreads out in all directions, forming a giant papyrus swamp called the Sudd (the barrier). The total area of the great swamps of the upper Nile can never be measured with precision since their size varies with the season, governed by the fluctuations in outfall from the equatorial lakes. But the size has been estimated to range from 16,931 km2 to 30,600 km2 during the rainy season, and the permanent swamp area is about 6,000 km2. As the river moves through the Sudd it loses about one-half of its total discharge - approximately 14 bcm - through evaporation, but maintains sufficient velocity to cut a slow meandering 600 km course until it reaches Lake No. There it is joined by other tributaries: the Behr el-Ghazal, which receives its water from Zaire, and the Behr el-Arab and Lo Rivers of western Sudan. Known then as the White Nile, the river jogs east, picks up the flow of the Sobat River that rises in the Ethiopian Highlands, and turns to Malakal, 3,832 km from the river's mouth. From this point to Khartoum (the convergence point of the White and the Blue Nile Rivers), a distance of 807 km, the White Nile receives no additional water. The Blue Nile flows from the highlands of Ethiopia and is strongly seasonal, subject to the annual monsoons streaming in from the Indian Ocean. The principal source of the Blue Nile is Lake Tana, but over its course, it picks up the flow of two seasonal tributaries, the Dinder and the Rahad. The Blue Nile flows approximately 2,500 km from its headwaters to Khartoum. Flowing downstream from Khartoum is the main Nile itself. Except for the seasonal discharge of the Atbara River that enters 320 km north of Khartoum, the Nile receives no perennial sources of water over the rest of its 3,000 km journey to the sea. This is the longest stretch of river in the world for which this can be said, and is all the more notable considering the flow is through the eastern reaches of the largest desert in the world, the Sahara. All waters of the Nile are derived from rainfall upon the Ethiopian plateau and upon the hinterlands of the Equatorial lakes. As one moves downstream from these regions annual precipitation declines in volume and increases in variability. While rainfall at the headwaters of both Niles is abundant it is by no means consistent. The seasonal rainfall fluctuations in the Blue Nile headwater region of Ethiopia are much more marked than those prevailing at the source of the White Nile. During the summer months (the flood season) the Blue Nile predominates, accounting for some 90 percent of the united river's flow, an average of 10 bcm per month. During the winter and spring months (the dry season), however, the Blue Nile delivers no more than 0.5 bcm per month, so it is the White Nile that sustains the flow with its delivery of about 2 bcm per month. (See Figure 6, also see Maps 6 and 7 in appendix.) In sum, approximately 86 percent of the Nile's flow originates in Ethiopia: the Blue Nile contributes 73 percent and the Atbara 13 percent. The other 14 percent is contributed by the White Nile. The united Nile's annual delivery to Aswan generally ranges from 80 bcm to 90 bcm. However, depending on the vagaries of the monsoonal weather over Ethiopia, the variation can be much greater. This is the heart of the matter: the total volume of water available in any given year is subject to substantial hydrologic variability. Precipitation over the Nile basin, and consequently Nile discharge, has fluctuated both historically and prehistorically. Figure 6. Relative Contributions of the White Nile, Blue Nile, and Atbara Tributaries to the Main Nile River.
Substantial variations in Nile precipitation have occurred on long (>1,000 year) and short (<10 year) timescales. In the past, these variant factors have been exclusively natural in origin, but the progressive human impact on the global environment over recent centuries has now led to the possibility of anthropogenic forcing of Nile Basin precipitation. In other words, natural processes are affected by human practices. The magnitude of historical fluctuations in Nile discharge experienced both in this century and in previous millennia is unlikely to be lessened in the future. Regional land-cover changes, agricultural and urban development, population explosion, and increased global greenhouse gas concentrations may well increase the amplitude of such fluctuations to main Nile discharge. Any future management plan of the Nile must consider these factors. Basinwide Management The most broad approach to integrated water management addresses the interrelationships between water and social and economic development. At this basinwide management level, interest lies in overarching policies and practices that can benefit all riparian countries within the basin. The concern is to determine the extent to which water is both an opportunity for and a barrier against development, and to ensure that water is managed and used such that social and economic growth may be sustained over the long term. The multiplicity of nations represents both the single most powerful obstacle to basinwide development planning as well as the most compelling argument favoring such an approach. Almost all countries in the Nile basin face a number of environmental problems, such as deforestation, soil erosion, and sedimentation, as well as social and political problems, such as lack of appropriate institutions, financial resources, and trained manpower for environmental protection and management. These problems, coupled with poverty and high population growth, pose serious threats to the water resource and hence the life support system of the basin's environment. It is therefore important that all Nile basin states pool their efforts to protect the environment and avert disasters such as drought, famine, desertification, and floods. Optimal development of the basin's water resources depends on agreement and cooperation between individual countries that share several common difficulties. Among them are population growth, insufficient agricultural production, and evaporative losses. These all directly impact the available water supply for all basin countries. An integrated approach to resolving these issues is most logical given the fact that all countries have a stake in the outcome. In addition, since these dilemmas transcend international boundaries, any action taken by one nation will almost assuredly impact other nations in the region. Prior to a discussion of the benefits and constraints associated with a basinwide management approach, the major problems driving the need for such an approach must first be addressed. Population Not surprisingly, as population grows and demand increases, so does the pressure on freshwater supplies and the capacity for conflicts. "In many countries in the Nile basin population growth, often at about 3 per cent per annum, is on a collision course with water resources." Population growth is the most fundamental constraint aggravating the water shortage in the Nile basin. Increased populations affect the demand for water in several ways. A larger population will need more water for human consumption, for livestock, and for industrial and commercial activities. Population growth increases the demand for food, and hence for irrigation and agricultural development. In water scarce countries, population size and consumption patterns will determine quality of life. As a consequence, the Nile riparians' freshwater needs to support health, quality of life, and socioeconomic development are rapidly increasing. Until recent years the use of Nile water has gradually increased, keeping pace with the increase in population. The nine Nile basin states are, however, faced with the prospect of continuing population increases, but with only limited further water available. The population increase in these regions with already high levels of water scarcity may be expected to generate water crises as increased numbers of humans will impact both water quantity and quality. The populations of Egypt, the Sudan, and Ethiopia have grown steadily since 1960. Egypt's population alone grows by another million people every nine months. By the year 2025, Ethiopia is forecast to have a population of approximately 122 million, 20 percent higher than that of Egypt. Along with the Nile countries themselves, pressure is added by the fact that the Horn of Africa harbors one of the world's largest refugee populations. In total, the population of co-basin states is expected to reach 812 million from the present 246 million by the year 2040. Close relationships exist between water resources, population health and land use. (See Graphs 1, 2, and 3.) A growing population needs not only water, but also biomass to provide food, fodder, fuelwood, and timber: the demographic element of food supply will continue to undermine the attempts of all governments to meet food demands. Water scarcity may constrain land-use options through the risk of crop failures and water supply problems caused by growing populations and industrial sectors. In addition, headwater resources of the Nile have not been extensively developed - the main development has taken place in the semi-arid and arid zones of the basin - where water is most lacking. In view of Egypt's population growth and arid climate, Lake Nasser (the storage reservoir created by the Aswan High Dam) by itself cannot provide Egypt with the total hydrological and agricultural security that was the original rationale for the High Dam. Population increases will also require Ethiopia and the Sudan to Graph 1. Egyptian Agricultural Production and Population.
Graph 2. Ethiopian Agricultural Production and Population.
Graph 3. Sudanese Agricultural Production and Population.
expand food production dramatically, but there are few avenues open to Ethiopia for such expansion, and the Sudan will require greater amounts of irrigation water - amounts that do not exist. Given the current co-basin's population growth, the question to be asked is whether they will be able to maintain a reasonable degree of food self sufficiency or whether they will become dependent on food imports. Among the basin states, seven are least developed countries with per capita annual income ranging from 120 to 310 US dollars. The relationship between population growth and poverty is important - if the growth of the economy is not sufficient to absorb and remunerate rapidly expanding labor forces, poverty will not be reduced. The Nile basin countries have a very low financial base and are internationally indebted. Rapid population growth combined with international debt begs the question of whether meaningful economic development is possible. Reducing population growth would be the single most beneficial development in terms of addressing problems of feeding populations and enabling the formulation of sustainable and economic water use policies. Controlling population growth would also reduce political tensions over water availability. It is urgent that a conceptual framework be developed linking population, including its sociocultural systems, with the various functions of water in the landscape, elaborating the connection between environment and development. Increases in populations and demand for higher standards of living dictate that natural resources be developed to the maximum benefit of humankind. Agriculture/Irrigation Even more than population pressure, yet directly linked, agriculture lies behind most of the region's water problems. Given the present composition of their overall economies, the major determinant of the water balance remains the agricultural sector. The Nile has provided the basis of agricultural development in Egypt and the Sudan since the start of agriculture about 7,000 years ago, and for political reasons, most East African nations have adopted policies of self-sufficiency when dealing with food supplies. In the Nile basin agriculture accounts for at least 80% of all water consumption. (See Maps 8, 9, and 10 in appendix.) Whereas a few liters of water per day are a basic minimum for human survival, at least a ton per day is required to produce the food needed for a reasonable diet for just one person. Ideally, all of the water used for agriculture should be passed through a crop on its way into the atmosphere or to sea, and much of it actually is. However, that does not necessarily mean that it is used most efficiently. There is little doubt that the most dramatic improvements in the use of water can be made in the agricultural sector. To begin with, certain current water use practices should be discouraged. Among these are the irrigated production of water-guzzling crops in arid regions that can readily be imported from water-rich regions; and the continued reliance on inefficient irrigation methods that tend to waterlog and salinize the soil. For example, in Egypt, the growing of rice and sugar cane, which both require a great deal of water, is questionable. In the hot climate, the return on agricultural yield per unit of water evaporated is poor and thus inefficient. Also, the most prevalent method of irrigation in the region is still the surface flooding of basins or furrows, a process that has, at best, a 50 percent efficiency. This irrigation technique involves the needless percolation or runoff of half or more of the water delivered. As viable alternatives, sprinkler irrigation can be operated at an efficiency of 70 percent or more, while drip irrigation can attain an efficiency as high as 90 percent if competently managed. Agriculture has a significant impact on water - it influences not only the quality of water passing on to downstream parts of the river basin, but flow as well. Land use also involves waste handling and the output of chemicals to the atmosphere, the land, and the water bodies, polluting the water circulating in the system. Proper management, therefore, demands that land and water management be integrated. As a result, the basin nations need to cooperate with each other in their respective agricultural planning. A partial solution could lie in the distribution of different crops to areas of the basin where they would be most bountiful. For example, water intensive or long season crops could be grown in the upper basin while crops requiring less water and growing time could be produced in the lower basin. Agricultural trades between the states could then ensue.
Evaporation The heavy evaporation and general dryness of the climate in Egypt and most of the Sudan have severe implications. (See Figure 7.) For example, substantial water losses from the surface of Lake Nasser occur, which, estimated at about 10 x 109 m3 per year, eliminate approximately 10% of the reservoir's net storage volume. In southern Sudan, enormous amounts of water, estimated to total at least 20 bcm, are lost in the Sudd swamps each year. As if those facts are not alarming enough, evaporation losses are likely to increase over the next century. Although these may be partially compensated for by the increased precipitation yield over the White Nile catchment, the need for completion of water preservation projects and other planned water conservation methods is implied. Measures to reduce evaporative losses have been under consideration for many years; however, substantial political, social, and environmental problems are associated with most of the proposals and have thus far blocked most efforts. Opportunities exist that could substantially reduce evaporative losses in the Nile basin. Storing more of the rivers' waters in Ethiopian highland reservoirs, where evaporation is much lower than in Egypt's Lake Nasser, could result in more water for all downstream countries. Shifting the major storage from Lake Nasser to reservoirs located in Ethiopia would reduce water losses not only because the climate in Ethiopia is less evaporative than the desert climate of Egypt, but also because the topography of the Blue Nile gorge in Ethiopia allows for a more favorable volume-to-surface ratio. The proposed upstream reservoirs would also regulate the water flow to the possible benefit of both upstream and downstream users. Other opportunities for cooperation exist in the Sudan. The reservoir behind the Jebel Aulia Dam on the White Nile, 40 km south of Khartoum, has annual evaporation losses of about 2.8 bcm. Elimination of this reservoir would substantially reduce these losses. Works upstream in the Southern Sudan could substantially increase the total water available by draining the marshes of the Sudd. The potential yield from Sudd projects could provide an additional 14 km3 per annum. Finally, over 200 possible water storage combinations exist in the upper riparian states, which would significantly reduce water losses from evaporation. However, implementing any one of them will require accord and cooperation between all basin countries. All Nile countries, in the long term, would benefit by working together to reduce evaporative losses on a basinwide scale. Figure 7. Evaporation's Effect on Water Supplies.
Constraints to Basinwide Planning Nile Waters Agreements The quest for basinwide management was actually begun by the British, who held sway over the greater part of the Nile basin until the middle of the twentieth century. Their idea was to develop the entire basin in an integrated fashion, through a series of dams controlling the outflow from the equatorial lakes feeding both tributaries and a canal for the White Nile to bypass the Sudd. Prospects for the comprehensive integrated development of the Nile basin dimmed when British colonialism ended and the newly independent basin nations began to assert their distinct national interests. From 1898 until the late 1940's attention on the waters of the Nile focused almost entirely on the irrigation needs of Egypt and the Sudan. The possible future requirements of Ethiopia and the other basin nations were ignored. The countries at the headwaters of the Nile, with substantial annual rainfall, were not thought of as areas where irrigation might be needed, despite the unpredictability and uneven distribution of rainfall in some parts and a high level of aridity in others. The most recent, and most famous, accord was the Nile Waters Agreement of 1959. The agreement assumed the following availability and proposed allocations (in km3):
Map 2 - Nile Basin States Total Annual Water Withdrawals This map depicts the pattern of freshwater use in the Nile basin in cubic kilometers per year. (Source: World Resources Database, File WA22106.)
Map 3 - The Nile River Catchment Basin This map shows the outline of the Nile River Watershed area which represents ten percent of the entire African continent. (Source: Abate, p. 228.)
Map 4 - The Nile River in the Sudan and Ethiopia A closer look at the White Nile (flowing north toward Khartoum from the lacustrine states on the left), the Blue Nile (flowing north toward Khartoum from Lake Tana on the right), and the Atbara (meeting the main Nile north of Khartoum). (Source: Digital Chart of The World.)
Map 5 - The Nile in Egypt A closer view of the Nile river as it flows through Egypt. The High Dam at Aswan is represented (red triangle at Aswan) and Lake Nasser (the reservoir created by the dam) is shown. Note the locations of all major Egyptian cities along the river, and the fact that no water is introduced to the Nile in Egyptian territory. (Source: Digital Chart of the World.)
Map 6 - Intermittent Water in the Nile River Basin During the wet season flooding occurs all along the main Nile and its tributaries. During this time the Blue Nile contributes approximately ninety percent of the united Nile's flow. (Source: Digital Chart of the World.)
Map 7 - Permanent Water in the Nile River Basin During the dry season the floods recede and the desert returns. During the dry months the White Nile sustains the flow of the main Nile river. (Source: Digital Chart of the World. )
Map 8 - Annual Water Withdrawals for Agriculture The yearly water withdrawals for agriculture are linked to the annual crop production of the Nile states. Note that the areas which are most agriculturally intensive are also generally the most arid area of the Nile basin. (Source: World Resources Database, File WA22109.)
Map 9 - Annual Water Withdrawals for Domestic Use This map illustrates the yearly amounts of water used for domestic purposes in the Nile states. (Source: World Resources Database, File WA22109.)
Map 10 - Annual Water Withdrawals for Industrial Use This map depicts the yearly amounts of water used for industrial purposes in the Nile states. (Source: World Resources Database, File WA22109.)
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Rowe and Isam Mohammed Abdel-Magid, Handbook of Wastewater Reclamation and Reuse, (Boca Raton, FL: CRC Press, Inc., 1995), p. 32. World Resources Database, (Baltimore, MD: World Resources Institute, 1996), File WA22101. Daniel Butler, "A World in Hot Water," Accountancy, December 21, 1995, p. 28. Daniel Hillel, Rivers of Eden: The Struggle for Water and the Quest for Peach in the Middle East, (New York: Oxford University Press, 1994), p. 269. Ewan Anderson, "Making Waves on the Nile," Geographical Magazine, vol. 63, April, 1991, p. 11. Jan Hultin, "The Nile: Source of Life, Source of Conflict," in L. Ohlsson (ed.), Hydropolitics: Conflicts over Water as a Development Constraint, (London: Zed Books, Ltd., 1995), p. 30. The Jonglei Canal: Impact and Opportunity, ed. Paul Howell, et al. (New York: Cambridge University Press, 1988), p. 65. Z. Abate, "The Integrated Development of Nile Basin Waters," in P. P. Howell and J. A. Allan (eds.), The Nile: Sharing a Scarce Resource, (Cambridge: Cambridge University Press, 1994), p. 236. Falkenmark, "Middle East Hydropolitics: Water Scarcity and Conflicts in the Middle East," Ambio, vol. 18, no. 6, September, 1989, p. 351. Hillel, p. 210. Three sublevels beyond the three main management levels have also been described: (1) the normative level, where decisions are made regarding what ought to be done (this level identifies current and potential issues that may require attention); (2) the strategic level, where decisions are made regarding what can be done (this level considers the broadest possible range of variables which may be significant for coordinated management of water and associated land and environmental resources - it provides the most comprehensive view); and (3) the operational level, where decisions are made regarding what will be done (direct attention is given to a smaller number of variables that are believed to account for a substantial portion of management problems - this provides insight on a local/regional scale). Integration can and should occur at all of these levels. Source: Bruce Mitchell, "Integrated Water Management," Bruce Mitchell (ed.), Integrated Water Management: International Experiences and Perspectives, (London: Belhaven Press, 1990), pp. 2-4. Information in this section adapted from the following sources: John Waterbury, Hydropolitics of the Nile Valley, (New York: Syracuse University Press, 1979), pp. 4-10. R. O. Collins, "History, Hydropolitics, and the Nile: Nile Control: Myth or Reality?" in P. P. Howell and J. A. Allan (eds.), The Nile: Sharing a Scarce Resource, (Cambridge: Cambridge University Press, 1994), pp. 110-114. Hillel, pp. 111-119. 1 billion cubic meters (bcm) = 1 cubic kilometer (km3) Hillel, p. 119. Collins, p. 112. Hillel, p. 117. Ibid., p. 119. Ibid. Ibid., p. 118. Hultin, p. 31. Dale Whittington, et al., "Toward a New Nile Waters Agreement," in A. Dinar and E. Tusak Loehman (eds.), Water Quantity/Quality Management and Conflict Resolution: Institutions, Processes, and Economic Analyses, (Westport, CT: Praeger Publishers, 1995), p. 167. World Resources Database, Files FA18101 and HD16101. Ibid. Ibid. The Jonglei Canal: Impact and Opportunity, p. 71. Malin Falkenmark and Jan Lundqvist, "Looming Water Crisis: New Approaches," in L. Ohlsson (ed.), Hydropolitics: Conflicts over Water as a Development Constraint, (London: Zed Books, Ltd., 1995), p. 182. Hillel, p. 213. Asit Biswas, "Environmental Sustainability of Egyptian Agriculture: Problems and Perspective," Ambio, vol. 24, no. 1, February, 1995, p. 16. Hultin, p. 37. The Jonglei Canal: Impact and Opportunity, p. 80. Ibid., p. 82. B. Kabanda and P. Kahangire, "Irrigation and Hydro-power Potential and Water Needs in Uganda - an Overview," in P. P. Howell and J. A. Allan (eds.), The Nile: Sharing a Scarce Resource, (Cambridge: Cambridge University Press, 1994), p. 223. Masahiro Murakami, Managing Water for Peace in the Middle East: Alternative Strategies, (Tokyo: United Nations University Press, 1995), p. 61. Hillel, p. 115. Whittington, p. 169. R. Stoner, "Future Irrigation Planning in Egypt," in P. P. Howell and J. A. Allan (eds.), The Nile: Sharing a Scarce Resource, (Cambridge: Cambridge University Press, 1994), p. 199. The Jonglei Canal: Impact and Opportunity, p. 79. Falkenmark and Lundqvist, p. 191. P. Howell, "East Africa's Water Requirements: the Equatorial Nile Project and the Nile Waters Agreement of 1929. A Brief Historical Review," in P. P. Howell and J. A. Allan (eds.), The Nile: Sharing a Scarce Resource, (Cambridge: Cambridge University Press, 1994), p. 97. Hillel, p. 274. Hultin, p. 37. D. Knott and R. Hewett, "Water Resources Planning in the Sudan," in P. P. Howell and J. A. Allan (eds.), The Nile: Sharing a Scarce Resource, (Cambridge: Cambridge University Press, 1994), p. 209. David LeMarquand, International Rivers: The Politics of Cooperation, (Vancouver, BC: Water Research Centre, University of British Columbia, 1977), p. 18. Hillel, p. 283.