The 1959 Water Agreement divided the Nile waters as, Egypt - 55.5 BCM, Sudan - 18.5 BCM, Evaporation - 10.0 BCM, Ethiopia - Nothing and the Total - 84.0 BCM (Average flow 1912-1959). Oddly enough, the Ethiopians, in whose country the Blue Nile begins, were left out of the 1959 agreement entirely. About 95% of Egypt's population lives within twelve miles of the river. Following completion of the dam there have been extensive problems, ironically caused in part because the annual flood no longer occurs.
Agriculture
Agriculture in the delta has traditionally benefited from the water and silt deposited by the flood, which comes from eroding basalt lava in the Ethiopian highlands. This silt made the Nile delta one of the richest agricultural areas in the world and the basis of one of the most ancient human civilizations. Irrigation and more intensive farming, combined with inadequate drainage, has created swamps. The rise in water tables has led to accumulation of harmful salts, fertilizers, and pesticides in the upper layers of the soil. Farmers have been forced to use about a million tons of artificial fertilizer as a substitute for the nutrients that no longer fill the flood plain.
Poor drainage of the newly irrigated lands has led to soil saturation and increased salinity. Over half of Egypt's farmland is now rated medium to poor in quality. The high cost of developing drainage systems is the main problem, and Egypt lacks hard foreign investment currency. The water table has risen since the dam was built, increasing the danger of fertilizer and other agricultural waste products seeping into the river, which is the main source of drinking water for the local population. Why would the water table rise? All soil is permeable, so water will always leak out of the lake. The lake essentially forces water into the surrounding soils when it is full, and then water can flow back into the lake when it is low.
Increased diseases
The parasitic disease schistosomiasis has been associated with the stagnant water of the fields and the reservoir. Some studies indicate that the number of individuals affected has increased since the opening of the High Dam. Recall from the Theroux reading (National Geographic) that schistosomiasis has been present in the region for thousands of years, but the reservoir is a huge breeding ground.In some areas, the building of the Aswan dam caused an increased occurrence of schistosomiasis among the population -- from 21% to almost 100%. Similarly, the first cases of malaria in northern Africa happened after establishment of Lake Nasser. Mosquitoes need shallow stagnant water to breed, and the lakeshore is the perfect environment. The recent identification of West Nile virus also indicates a water-bred and mosquito-borne disease that would not flourish if Lake Nasser had not been built.
Changes to the Egyptian fishing industry
One good aspect of the lake was to be its contribution to a new Egyptian fishing industry. However, weeds flourished in the reservoir, causing problems for the dam and the generators. Five years after the dam was built, two thousand fishermen managed to catch 3,628 tons annually, while the catch was expected to be around 20,000 tons. Ten years later the catch had dropped to 907 tons, and in 1978 the fisheries were so poor that only a small part of the population was able to live off fishing.
The effect of the dam on the Mediterranean fishing industry was more dramatic. The silt and sediments normally carried by the river contain important minerals and nutrients for fisheries in the sea at the river mouth. Unlike more fertile, nutrient-rich seas, such as the North Sea and the Arabian Sea, the Mediterranean is noted for its nutrient-poor waters that contribute to a low level of primary productivity. Primary productivity is the creation of organic matter through photosynthesis by unicellular organisms called phytoplankton. In the Mediterranean Sea, primary productivity is unusually low for several reasons. The circulation of the sea brings low-nutrient water from the North Atlantic through the Strait of Gibraltar, and allows nutrient-rich bottom water to exit the sea through the same opening. The arid climate of the region and the low levels of nutrient-rich river runoff also contribute to the low productivity of the Mediterranean.
Before the High Dam was built, fifty percent of the Nile flow drained into the Mediterranean. During an average flood, the total discharge of nutrient salts was estimated to be approximately 5,500 tons of phosphate and 280,000 tons of silicate. The nutrient-rich floodwater, or Nile Stream, was ~15 kilometers wide; it extended along the Egyptian coast and was detected off the Israeli coast and sometimes off southern Turkey.
The decrease in fertility of the southeastern Mediterranean waters caused by the High Dam has had a catastrophic effect on marine fisheries. The average fish catch declined from nearly 35,000 tons in 1962 and 1963 to less than one-fourth of this catch in 1969. Hardest hit was the sardine fishery: from a total of 18,000 tons in 1962, a mere 460 and 600 tons of sardine were landed in 1968 and 1969. The shrimp fishery also took a heavy toll as the catch decreased from 8,300 tons in 1963 to 1,128 tons in 1969.
Erosion of the Delta
The reduced supply of silt and sediment from the annual flood has caused heavy erosion in the Nile Delta and as far away as Israel. The erosion, coupled with normal compaction of deltaic sediments, has decreased the inhabitable land on the Delta for the first time in over 10,000 years. The lack of silt reaching the Delta has made for a different set of problems farther upriver as well. The silt now gets trapped behind the Aswan Dam, where it settles out of the water and falls in thick layers on the floor of Lake Nasser. As a result, the reservoir becomes smaller each year, and is less able to handle the water and electricity-generation needs of the nation.
The Jonglei Canal
Where can more water be found? Ironically, the waters of the White Nile in southern Sudan likely hold the key to the economies of both Egypt and the Sudan (see maps below).
In southern Sudan, the flat topography has created a vast swamp known as the Sudd--a huge area where the White Nile meanders towards Malakal. The Sudd covers about 6,370 square miles in the dry winter months and roughly doubles in area during the summer rains. The White Nile gets stalled in the Sudd, and about 17 BCM of water is lost through evaporation and transpiration. The idea of digging a canal through the Sudd in order to speed flow of the water is a current political issue, but proposals for the Jonglei Canal, and other major Nile Basin projects, go back generations.
The digging of the Jonglei Canal began in 1978. A famous (no kidding) excavating machine known as the "Bucketwheel" was brought in from Pakistan, where it had dug a 101-km canal between the Indus and Jhelum rivers. Sudanese hydrologist Yahia Abdel Magid refurbished the Bucketwheel and brought it to Sudan. It is the largest excavator in the world, weighing over 2,100 tons. It has 12 giant buckets (3 cubic meters each) hung on a circular wheel (12.5 meters in diameter) which dig earth, then dump it onto a transmission belt, which deposits it on the bank. At full speed, the Bucketwheel can excavate 2 km a week but requires (10,000 gallons) of gasoline per 24 hours.
The Jonglei Canal project was considered one of the most important integration projects between Egypt and Sudan. The project was designed to make full use of the Nile, promote human and economic development in isolated regions, and boost agricultural development in both countries. In 1983, work was suspended as a result of the Sudanese civil war, and a missile launched by an unknown source destroyed the Bucketwheel. As a result, only the northern 180 km of the 360-km planned manmade channel is completed. Worse yet, the completed portion of the Jonglei Canal is drying out and falling apart.
Despite the possible benefits of having more irrigated farmland, the canal could have a devastating effect on the swampland environment and the people who live there. For example, draining water from the Sudd would reduce the swamp area by an estimated 36%, reducing the mosquito habitat (good), but also reducing the wetlands appropriate for grazing and wildlife habitat. Roughly two million people live in the area, and their livelihoods would be altered. Today they are dominantly semi-nomadic and move homes and livestock throughout the year. Land that has been under water for more than 20 years could be reclaimed, providing ideal ground for breeding cattle, while the canal itself would have provided new opportunities for fishing.
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