Aswan High Dam
   HOME

TheInfoList



OR:

The Aswan Dam, or Aswan High Dam, is one of the world's largest embankment dams, which was built across the
Nile The Nile (also known as the Nile River or River Nile) is a major north-flowing river in northeastern Africa. It flows into the Mediterranean Sea. The Nile is the longest river in Africa. It has historically been considered the List of river sy ...
in Aswan, Egypt, between 1960 and 1970. When it was completed, it was the tallest earthen dam in the world, surpassing the Chatuge Dam in the United States. The dam, which created the
Lake Nasser Lake Nasser ( ', ) is a large reservoir (water), reservoir in southern Egypt and northern Sudan. It was created by the construction of the Aswan Dam, Aswan High Dam and is one of the List of reservoirs by volume, largest man-made lakes in the wo ...
reservoir, was built upstream of the Aswan Low Dam, which had been completed in 1902 and was already at its maximum utilization. Construction of the High Dam became a key objective of the military regime that took power following the 1952 Egyptian revolution. With its ability to better control flooding, provide increased water storage for irrigation and generate
hydroelectricity Hydroelectricity, or hydroelectric power, is Electricity generation, electricity generated from hydropower (water power). Hydropower supplies 15% of the world's electricity, almost 4,210 TWh in 2023, which is more than all other Renewable energ ...
, the dam was seen as pivotal to Egypt's planned
industrialization Industrialisation (British English, UK) American and British English spelling differences, or industrialization (American English, US) is the period of social and economic change that transforms a human group from an agrarian society into an i ...
. Like the earlier implementation, the High Dam has had a significant effect on the
economy An economy is an area of the Production (economics), production, Distribution (economics), distribution and trade, as well as Consumption (economics), consumption of Goods (economics), goods and Service (economics), services. In general, it is ...
and culture of Egypt. Before the High Dam was built, even with the old dam in place, the annual
flooding of the Nile The flooding of the Nile (commonly referred to as ''the Inundation'') and its silt Deposition (geology), deposition was a natural cycle first attested in Ancient Egypt. It was of singular importance in the history and culture of Egypt. Governments ...
during late summer had continued to pass largely unimpeded down the valley from its
East Africa East Africa, also known as Eastern Africa or the East of Africa, is a region at the eastern edge of the Africa, African continent, distinguished by its unique geographical, historical, and cultural landscape. Defined in varying scopes, the regi ...
n
drainage basin A drainage basin is an area of land in which all flowing surface water converges to a single point, such as a river mouth, or flows into another body of water, such as a lake or ocean. A basin is separated from adjacent basins by a perimeter, ...
. These floods brought high water with natural
nutrient A nutrient is a substance used by an organism to survive, grow and reproduce. The requirement for dietary nutrient intake applies to animals, plants, fungi and protists. Nutrients can be incorporated into cells for metabolic purposes or excret ...
s and
mineral In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid substance with a fairly well-defined chemical composition and a specific crystal structure that occurs naturally in pure form.John P. Rafferty, ed. (2011): Mi ...
s that annually enriched the fertile
soil Soil, also commonly referred to as earth, is a mixture of organic matter, minerals, gases, water, and organisms that together support the life of plants and soil organisms. Some scientific definitions distinguish dirt from ''soil'' by re ...
along its floodplain and
delta Delta commonly refers to: * Delta (letter) (Δ or δ), the fourth letter of the Greek alphabet * D (NATO phonetic alphabet: "Delta"), the fourth letter in the Latin alphabet * River delta, at a river mouth * Delta Air Lines, a major US carrier ...
; this predictability had made the Nile valley ideal for farming since ancient times. However, this natural flooding varied, since high-water years could destroy the whole
crop A crop is a plant that can be grown and harvested extensively for profit or subsistence. In other words, a crop is a plant or plant product that is grown for a specific purpose such as food, Fiber, fibre, or fuel. When plants of the same spe ...
, while low-water years could create widespread
drought A drought is a period of drier-than-normal conditions.Douville, H., K. Raghavan, J. Renwick, R.P. Allan, P.A. Arias, M. Barlow, R. Cerezo-Mota, A. Cherchi, T.Y. Gan, J. Gergis, D.  Jiang, A.  Khan, W.  Pokam Mba, D.  Rosenfeld, J. Tierney, ...
and consequently famine. Both these events had continued to occur periodically. As Egypt's population grew and technology increased, both a desire and the ability developed to completely control the flooding, and thus both protect and support farmland and its economically important
cotton Cotton (), first recorded in ancient India, is a soft, fluffy staple fiber that grows in a boll, or protective case, around the seeds of the cotton plants of the genus '' Gossypium'' in the mallow family Malvaceae. The fiber is almost pure ...
crop. With the greatly increased
reservoir A reservoir (; ) is an enlarged lake behind a dam, usually built to water storage, store fresh water, often doubling for hydroelectric power generation. Reservoirs are created by controlling a watercourse that drains an existing body of wa ...
storage provided by the High Aswan Dam, the floods could be controlled and the water could be stored for later release over multiple years. The Aswan Dam was designed by Nikolai Aleksandrovich Malyshev of the Moscow-based Hydroproject Institute. Designed for both irrigation and power generation, the dam incorporates a number of relatively new features, including a very deep grout curtain below its base. Although the reservoir will eventually silt in, even the most conservative estimates indicate the dam will give at least 200 years of service.


Construction history

The earliest recorded attempt to build a dam near Aswan was in the 11th century, when the Arab polymath and engineer Ibn al-Haytham (known as ''Alhazen'' in the West) was summoned to Egypt by the Fatimid Caliph, Al-Hakim bi-Amr Allah, to regulate the
flooding of the Nile The flooding of the Nile (commonly referred to as ''the Inundation'') and its silt Deposition (geology), deposition was a natural cycle first attested in Ancient Egypt. It was of singular importance in the history and culture of Egypt. Governments ...
, a task requiring an early attempt at an Aswan Dam. His field work convinced him of the impracticality of this scheme.


Aswan Low Dam, 1898–1902

The British began construction of the first dam across the Nile in 1898. Construction lasted until 1902 and the dam was opened on 10 December 1902. The project was designed by Sir William Willcocks and involved several eminent engineers, including Sir Benjamin Baker and Sir John Aird, whose firm, John Aird & Co., was the main contractor.


Aswan High Dam prelude, 1954–1960

In 1952, the Greek-Egyptian engineer Adrian Daninos began to develop the plan of the new Aswan Dam. Although the Low Dam was almost overtopped in 1946, the government of King Farouk showed no interest in Daninos's plans. Instead the Nile Valley Plan by the British hydrologist Harold Edwin Hurst was favored, which proposed to store water in Sudan and Ethiopia, where evaporation is much lower. The Egyptian position changed completely after the overthrow of the monarchy, led by the Free Officers Movement including Gamal Abdel Nasser. The Free Officers were convinced that the Nile Waters had to be stored in Egypt for political reasons, and within two months, the plan of Daninos was accepted. Initially, both the
United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...
and the
USSR The Union of Soviet Socialist Republics. (USSR), commonly known as the Soviet Union, was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 until Dissolution of the Soviet ...
were interested in helping development of the dam. Complications ensued due to their rivalry during the
Cold War The Cold War was a period of global Geopolitics, geopolitical rivalry between the United States (US) and the Soviet Union (USSR) and their respective allies, the capitalist Western Bloc and communist Eastern Bloc, which lasted from 1947 unt ...
, as well as growing intra-Arab tensions. In 1955, Nasser was claiming to be the leader of Arab nationalism, in opposition to the traditional monarchies, especially the
Hashemite The Hashemites (), also House of Hashim, are the Dynasty, royal family of Jordan, which they have ruled since 1921, and were the royal family of the kingdoms of Kingdom of Hejaz, Hejaz (1916–1925), Arab Kingdom of Syria, Syria (1920), and Kingd ...
Kingdom of Iraq following its signing of the 1955 Baghdad Pact. At that time the U.S. feared that
communism Communism () is a political sociology, sociopolitical, political philosophy, philosophical, and economic ideology, economic ideology within the history of socialism, socialist movement, whose goal is the creation of a communist society, a ...
would spread to the Middle East, and it saw Nasser as a natural leader of an anticommunist procapitalist
Arab League The Arab League (, ' ), officially the League of Arab States (, '), is a regional organization in the Arab world. The Arab League was formed in Cairo on 22 March 1945, initially with seven members: Kingdom of Egypt, Egypt, Kingdom of Iraq, ...
. America and the United Kingdom offered to help finance construction of the High Dam, with a loan of $270 million, in return for Nasser's leadership in resolving the Arab-Israeli conflict. While opposed to communism, capitalism, and imperialism, Nasser identified as a tactical neutralist, and sought to work with both the U.S. and the USSR for Egyptian and Arab benefit. After the UN criticized a raid by Israel against Egyptian forces in Gaza in 1955, Nasser realized that he could not portray himself as the leader of pan-Arab nationalism if he could not defend his country militarily against Israel. In addition to his development plans, he looked to quickly modernize his military, and he turned first to the U.S. for aid. American Secretary of State John Foster Dulles and President Dwight Eisenhower told Nasser that the U.S. would supply him with weapons only if they were used for defensive purposes and if he accepted American military personnel for supervision and training. Nasser did not accept these conditions, and consulted the USSR for support. Although Dulles believed that Nasser was only bluffing and that the USSR would not aid Nasser, he was wrong: the USSR promised Nasser a quantity of arms in exchange for a deferred payment of Egyptian grain and cotton. On 27 September 1955, Nasser announced an arms deal, with
Czechoslovakia Czechoslovakia ( ; Czech language, Czech and , ''Česko-Slovensko'') was a landlocked country in Central Europe, created in 1918, when it declared its independence from Austria-Hungary. In 1938, after the Munich Agreement, the Sudetenland beca ...
acting as a middleman for the Soviet support. Instead of attacking Nasser for turning to the Soviets, Dulles sought to improve relations with him. In December 1955, the US and the UK pledged $56 and $14 million, respectively, toward construction of the High Aswan Dam.Dougherty, p. 22 Though the Czech arms deal created an incentive for the US to invest at Aswan, the UK cited the deal as a reason for repealing its promise of dam funds. Dulles was angered more by Nasser's diplomatic recognition of
China China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...
, which was in direct conflict with Dulles's policy of containment of communism. Several other factors contributed to the US deciding to withdraw its offer of funding for the dam. Dulles believed that the USSR would not fulfill its commitment of military aid. He was also irritated by Nasser's neutrality and attempts to play both sides of the
Cold War The Cold War was a period of global Geopolitics, geopolitical rivalry between the United States (US) and the Soviet Union (USSR) and their respective allies, the capitalist Western Bloc and communist Eastern Bloc, which lasted from 1947 unt ...
. At the time, other Western allies in the Middle East, including Turkey and Iraq, were resentful that Egypt, a persistently neutral country, was being offered so much aid. In June 1956, the Soviets offered Nasser $1.12 billion at 2% interest for the construction of the dam. On 19 July the U.S. State Department announced that American financial assistance for the High Dam was "not feasible in present circumstances."Dougherty, p. 22 On 26 July 1956, with wide Egyptian acclaim, Nasser announced the nationalization of the Suez Canal that included fair compensation for the former owners. Nasser planned on the revenues generated by the canal to help fund construction of the High Dam. When the Suez War broke out, the United Kingdom, France, and Israel seized the canal and the Sinai. But pressure from the U.S. and the
USSR The Union of Soviet Socialist Republics. (USSR), commonly known as the Soviet Union, was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 until Dissolution of the Soviet ...
at the
United Nations The United Nations (UN) is the Earth, global intergovernmental organization established by the signing of the Charter of the United Nations, UN Charter on 26 June 1945 with the stated purpose of maintaining international peace and internationa ...
and elsewhere forced them to withdraw. In 1958, the USSR proceeded to provide support for the High Dam project. In the 1950s, archaeologists began raising concerns that several major historical sites, including the famous temple of
Abu Simbel Abu Simbel is a historic site comprising two massive Rock-cut architecture, rock-cut Egyptian temple, temples in the village of Abu Simbel (village), Abu Simbel (), Aswan Governorate, Upper Egypt, near the border with Sudan. It is located on t ...
were about to be submerged by waters collected behind the dam. A rescue operation began in 1960 under
UNESCO The United Nations Educational, Scientific and Cultural Organization (UNESCO ) is a List of specialized agencies of the United Nations, specialized agency of the United Nations (UN) with the aim of promoting world peace and International secur ...
(for details see below under Effects). Despite its size, the Aswan project has not materially hurt the Egyptian balance of payments. The three Soviet credits covered virtually all of the project's foreign exchange requirements, including the cost of technical services, imported power generating and transmission equipment and some imported equipment for land reclamation. Egypt was not seriously burdened by payments on the credits, most of which were extended for 12 years with interest at the very low rate of 2-1/2%. Repayments to the
USSR The Union of Soviet Socialist Republics. (USSR), commonly known as the Soviet Union, was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 until Dissolution of the Soviet ...
constituted only a small net drain during the first half of the 1960s, and increased export earnings derived from crops grown on newly reclaimed land have largely offset the modest debt service payments in recent years. During 1965–1970, these export earnings amounted to an estimated $126 million, compared with debt service payments of $113 million.


Construction and filling, 1960–1976

The Soviets also provided technicians and heavy machinery. The enormous rock and clay dam was designed by Nikolai Aleksandrovich Malyshev of the Moscow-based Hydroproject Institute, along with some Egyptian engineers. 25,000 Egyptian engineers and workers contributed to the construction of the dams. Originally designed by West German and French engineers in the early 1950s and slated for financing with Western credits, the Aswan High Dam became the USSR's largest and most famous foreign aid project after the United States, the United Kingdom, and the International Bank for Reconstruction and Development (IBRD) withdrew their support in 1956. The first Soviet loan of $100 million to cover construction of coffer dams for diversion of the Nile was extended in 1958. An additional $225 million was extended in 1960 to complete the dam and construct power-generating facilities, and subsequently about $100 million was made available for land reclamation. These credits of some $425 million covered only the foreign exchange costs of the project, including salaries of Soviet engineers who supervised the project and were responsible for the installation and testing of Soviet equipment. Actual construction, which began in 1960, was done by Egyptian companies on contract to the High Dam Authority, and all domestic costs were borne by the Egyptians. Egyptian participation in the venture has raised the construction industry's capacity and reputation significantly. On the Egyptian side, the project was led by Osman Ahmed Osman's Arab Contractors. The relatively young Osman underbid his only competitor by one-half. * 1960: Start of construction on 9 January * 1964: First dam construction stage completed, reservoir started filling * 1970: The High Dam, ''as-Sad al-'Aali'', completed on 21 July * 1976: Reservoir reached capacity.


Specifications

The Aswan High Dam is long, wide at the base, wide at the crest and tall. It contains of material. At maximum, of water can pass through the dam. There are further emergency spillways for an extra , and the Toshka Canal links the reservoir to the Toshka Depression. The reservoir, named
Lake Nasser Lake Nasser ( ', ) is a large reservoir (water), reservoir in southern Egypt and northern Sudan. It was created by the construction of the Aswan Dam, Aswan High Dam and is one of the List of reservoirs by volume, largest man-made lakes in the wo ...
, is long and at its widest, with a surface area of . It holds of water.


Irrigation scheme

Due to the absence of appreciable rainfall, Egypt's agriculture depends entirely on
irrigation Irrigation (also referred to as watering of plants) is the practice of applying controlled amounts of water to land to help grow crops, landscape plants, and lawns. Irrigation has been a key aspect of agriculture for over 5,000 years and has bee ...
. With irrigation, two harvests per year are possible, except for sugar cane which has a growing period of almost one year. The high dam at Aswan releases, on average, water per year, of which some are diverted into the irrigation canals. In the Nile valley and delta, almost benefit from these waters producing on average 1.8 crops per year. The annual crop consumptive use of water is about . Hence, the overall irrigation efficiency is 38/46 = 0.826 or 83%. This is a relatively high irrigation efficiency. The field irrigation efficiencies are much less, but the losses are reused downstream. This continuous reuse accounts for the high overall efficiency. The following table shows the distribution of irrigation water over the branch canals taking off from the one main irrigation canal, the Mansuriya Canal near Giza. :* Period 1 March to 31 July. 1
feddan A feddan () is a unit of area used in Egypt, South Sudan, Sudan, Syria, and Oman. In Classical Arabic, the word means 'a yoke of oxen', implying the area of ground that could be tilled by oxen in a certain time. In Egypt, the feddan is the only n ...
is 0.42 ha or about 1 acre. :* Data from the Egyptian Water Use Management Project (EWUP) The salt concentration of the water in the Aswan reservoir is about , a very low salinity level. At an annual inflow of , the annual salt influx reaches 14 million tons. The average salt concentration of the drainage water evacuated into the sea and the coastal lakes is . At an annual discharge of (not counting the of salt intrusion from the sea and the lakes, see figure "Water balances"), the annual salt export reaches 27 million ton. In 1995, the output of salt was higher than the influx, and Egypt's agricultural lands were desalinizing. Part of this could be due to the large number of subsurface drainage projects executed in the last decades to control the water table and
soil salinity Soil salinity is the salt (chemistry), salt content in the soil; the process of increasing the salt content is known as salinization (also called salination in American and British English spelling differences, American English). Salts occur nat ...
. Drainage through subsurface drains and drainage channels is essential to prevent a deterioration of crop yields from waterlogging and soil salinization caused by irrigation. By 2003, more than have been equipped with a subsurface drainage system and approximately of water is drained annually from areas with these systems. The total investment cost in agricultural drainage over 27 years from 1973 to 2002 was about $3.1 billion covering the cost of design, construction, maintenance, research and training. During this period 11 large-scale projects were implemented with financial support from World Bank and other donors.


Effects

The High Dam has resulted in protection from floods and droughts, an increase in agricultural production and employment, electricity production, and improved navigation that also benefits tourism. Conversely, the dam flooded a large area, causing the relocation of over 100,000 people. Many archaeological sites were submerged while others were relocated. The dam is blamed for coastline erosion, soil salinity, and health problems. The assessment of the costs and benefits of the dam remains controversial decades after its completion. According to one estimate, the annual economic benefit of the High Dam immediately after its completion was , $587 million using the exchange rate in 1970 of $2.30 per : from agricultural production, from hydroelectric generation, from flood protection, and from improved navigation. At the time of its construction, total cost, including unspecified "subsidiary projects" and the extension of electric power lines, amounted to . Not taking into account the negative environmental and social effects of the dam, its costs are thus estimated to have been recovered within only two years. One observer notes: "The impacts of the Aswan High Dam (...) have been overwhelmingly positive. Although the Dam has contributed to some environmental problems, these have proved to be significantly less severe than was generally expected, or currently believed by many people." Another observer disagreed and he recommended that the dam should be torn down. Tearing it down would cost only a fraction of the funds required for "continually combating the dam's consequential damage" and of fertile land could be reclaimed from the layers of mud on the bed of the drained reservoir. Samuel C. Florman wrote about the dam: "As a structure it is a success. But in its effect on the ecology of the Nile Basin – most of which could have been predicted – it is a failure". Periodic floods and droughts have affected Egypt since ancient times. The dam mitigated the effects of floods, such as those in 1964, 1973, and 1988. Navigation along the river has been improved, both upstream and downstream of the dam. Sailing along the Nile is a favorite tourism activity, which is mainly done during the winter when the natural flow of the Nile would have been too low to allow navigation of cruise ships. A new fishing industry has been created around Lake Nasser, though it is struggling due to its distance from any significant markets. The annual production was about 35,000 tons in the mid-1990s. Factories for the fishing industry and packaging have been set up near the Lake. According to a 1971 CIA declassified report, although the High Dam has not created ecological problems as serious as some observers have charged, its construction has brought economic losses as well as gains. These losses derive largely from the settling in dam's lake of the rich silt traditionally borne by the Nile. To date (1971), the main impact has been on the fishing industry. Egypt's Mediterranean catch, which once averaged 35,000–40,000 tons annually, has shrunk to 20,000 tons or less, largely because the loss of
plankton Plankton are the diverse collection of organisms that drift in Hydrosphere, water (or atmosphere, air) but are unable to actively propel themselves against ocean current, currents (or wind). The individual organisms constituting plankton are ca ...
nourished by the silt has eliminated the sardine population in Egyptian waters. Fishing in high dam's lake may in time at least partly offset the loss of saltwater fish, but only the most optimistic estimates place the eventual catch as high as 15,000–20,000 tons. Lack of continuing silt deposits at the mouth of the river also has contributed to a serious erosion problem. Commercial fertilizer requirements and salination and drainage difficulties, already large in perennially irrigated areas of Lower and Middle Egypt, will be somewhat increased in Upper Egypt by the change to perennial irrigation.


Drought protection, agricultural production and employment

The dams also protected Egypt from the droughts in 1972–1973 and 1983–1987 that devastated East and West Africa. The High Dam allowed Egypt to reclaim about 2.0 million
feddan A feddan () is a unit of area used in Egypt, South Sudan, Sudan, Syria, and Oman. In Classical Arabic, the word means 'a yoke of oxen', implying the area of ground that could be tilled by oxen in a certain time. In Egypt, the feddan is the only n ...
(840,000 hectares) in the
Nile Delta The Nile Delta (, or simply , ) is the River delta, delta formed in Lower Egypt where the Nile River spreads out and drains into the Mediterranean Sea. It is one of the world's larger deltas—from Alexandria in the west to Port Said in the eas ...
and along the Nile Valley, increasing the country's irrigated area by a third. The increase was brought about both by irrigating what used to be desert and by bringing under cultivation of that were previously used as flood retention basins. About half a million families were settled on these new lands. In particular the area under rice and sugar cane cultivation increased. In addition, about 1 million feddan (420,000 hectares), mostly in Upper Egypt, were converted from flood irrigation with only one crop per year to perennial irrigation allowing two or more crops per year. On other previously irrigated land, yields increased because water could be made available at critical low-flow periods. For example, wheat yields in Egypt tripled between 1952 and 1991 and better availability of water contributed to this increase. Most of the 32 km3 of freshwater, or almost 40 percent of the average flow of the Nile that were previously lost to the sea every year could be put to beneficial use. While about 10 km3 of the water saved is lost due to evaporation in Lake Nasser, the amount of water available for irrigation still increased by 22 km3.M.A. Abu-Zeid & F. Z. El-Shibini:
Egypt's High Aswan Dam
", ''Water Resources Development'', Vol. 13, No. 2, pp. 209–217, 1997
Other estimates put evaporation from Lake Nasser at between 10 and 16 cubic km per year.


Electricity production

The dam powers twelve generators each rated at , with a total of . Power generation began in 1967. When the High Dam first reached peak output in 1970, it produced around half of Egypt's production of electric power (about 15 percent by 1998), and it gave most Egyptian villages the use of electricity for the first time. The High Dam has also improved the efficiency and the extension of the Old Aswan Hydropower stations by regulating upstream flows. At the time of completion, it was the largest power station in Africa and the 6th largest hydroelectric power station in the world. All High Dam power facilities were completed ahead of schedule. Twelve turbines were installed and tested, giving the plant an installed capacity of 2,100 megawatts (MW), or more than twice the national total in 1960. With this capacity, the Aswan plant can produce 10 billion kWh of energy yearly. Two 500-kilovolt trunk lines to Cairo have been completed, and initial transmission problems, stemming mainly from poor insulators, were solved. Also, the damage inflicted on a main transformer station in 1968 by Israeli commandos has been repaired, and the Aswan plant is fully integrated with the power network in Lower Egypt. By 1971 estimation, power output at Aswan won't reach much more than half of the plant's theoretical capacity, because of limited water supplies and the differing seasonal water-use patterns for
irrigation Irrigation (also referred to as watering of plants) is the practice of applying controlled amounts of water to land to help grow crops, landscape plants, and lawns. Irrigation has been a key aspect of agriculture for over 5,000 years and has bee ...
and power production.
Agricultural Agriculture encompasses crop and livestock production, aquaculture, and forestry for food and non-food products. Agriculture was a key factor in the rise of sedentary human civilization, whereby farming of domesticated species created f ...
demand for water in the summer far exceeds the amount needed to meet the comparatively low summer demand for electric power. Heavy summer irrigation use, however, will leave insufficient water under Egyptian control to permit hydroelectric power production at full capacity in the winter. Technical studies indicate that a maximum annual output of 5 billion kWh appears to be all that can be sustained due to fluctuations in Nile flows. Aswan High Dam electricity production is expected to be impacted by upstream mega-dams during extended drought periods.


Dangers

Inland flood events cause the highest number of casualties among all natural catastrophes - including the devastation of harvest, starvation, sickness and famine in the aftermath of floods. Millions of people have died in consequence of single flood events before. An estimated 2- 4 million people perished in consequence of the Yangtze–Huai River flood of 1931 including famine and epidemics in the following years. A flood in Egypt, caused by overtopping of AHD and the subsequent eroding of the dam, can be 20 times worse than the historic flood in China. Nasser Lake contains a water-volume that defies imagination and it would increase to 209 cubic kilometers during the events described in this study. Moreover, the flood caused by a dam breach is concentrated to plus/minus one day, instead of a seasonal flood distributed over 4 months. The short flood is much more violent. Millions of homes would be destroyed. Nationwide irrigation infrastructure would be covered by a layer of contaminated sediment that becomes hard as stone after a short while. After Nasser lake has disappeared (emptied), agricultural production would fall back to pre-AHD levels causing widespread famine for years.


Resettlement and compensations

Lake Nasser flooded much of lower
Nubia Nubia (, Nobiin language, Nobiin: , ) is a region along the Nile river encompassing the area between the confluence of the Blue Nile, Blue and White Nile, White Niles (in Khartoum in central Sudan), and the Cataracts of the Nile, first cataract ...
and 100,000 to 120,000 people were resettled in Sudan and Egypt. In Sudan, 50,000 to 70,000 Sudanese Nubians were moved from the old town of Wadi Halfa and its surrounding villages. Some were moved to a newly created settlement on the shore of Lake Nasser called New Wadi Halfa, and some were resettled approximately south to the semi-arid Butana plain near the town of Khashm el-Girba up the Atbara River. The climate there had a regular rainy season as opposed to their previous desert habitat in which virtually no rain fell. The government developed an irrigation project, called the New Halfa Agricultural Development Scheme to grow cotton, grains, sugar cane and other crops. The Nubians were resettled in twenty five planned villages that included schools, medical facilities, and other services, including piped water and some electrification. In Egypt, the majority of the 50,000 Nubians were moved three to ten kilometers from the Nile near Edna and Kom Ombo, downstream from Aswan in what was called "New Nubia". Housing and facilities were built for 47 village units whose relationship to each other approximated that in Old Nubia. Irrigated land was provided to grow mainly sugar cane. In 2019–20, Egypt started to compensate the Nubians who lost their homes following the dam impoundment.


Archaeological sites

Twenty-two monuments and architectural complexes that were threatened by flooding from Lake Nasser, including the
Abu Simbel Abu Simbel is a historic site comprising two massive Rock-cut architecture, rock-cut Egyptian temple, temples in the village of Abu Simbel (village), Abu Simbel (), Aswan Governorate, Upper Egypt, near the border with Sudan. It is located on t ...
temples, were preserved by moving them to the shores of the lake under the
UNESCO The United Nations Educational, Scientific and Cultural Organization (UNESCO ) is a List of specialized agencies of the United Nations, specialized agency of the United Nations (UN) with the aim of promoting world peace and International secur ...
Nubia Campaign.The Rescue of Nubian Monuments and Sites
, UNESCO project site about Nubia Campaign.
Also moved were Philae, Kalabsha and Amada. These monuments were granted to countries that helped with the works: * The Debod temple to Madrid * The
Temple of Dendur The Temple of Dendur (Dendoor in the 19th century) is a Roman Egyptian religious structure originally located in Tuzis (later Dendur), Nubia about south of modern Aswan. Around 23 BCE, Emperor Augustus commissioned the Egyptian temple, temple d ...
to the
Metropolitan Museum of Art The Metropolitan Museum of Art, colloquially referred to as the Met, is an Encyclopedic museum, encyclopedic art museum in New York City. By floor area, it is the List of largest museums, third-largest museum in the world and the List of larg ...
of New York * The Temple of Taffeh to the Rijksmuseum van Oudheden of
Leiden Leiden ( ; ; in English language, English and Archaism, archaic Dutch language, Dutch also Leyden) is a List of cities in the Netherlands by province, city and List of municipalities of the Netherlands, municipality in the Provinces of the Nethe ...
* The Temple of Ellesyia to the Museo Egizio of
Turin Turin ( , ; ; , then ) is a city and an important business and cultural centre in northern Italy. It is the capital city of Piedmont and of the Metropolitan City of Turin, and was the first Italian capital from 1861 to 1865. The city is main ...
These items were removed to the garden area of the Sudan National Museum of Khartoum: * The temple of Ramses II at Aksha * The temple of Hatshepsut at Buhen * The temple of Khnum at Kumma * The tomb of the Nubian prince Djehuti-hotep at Debeira * The temples of Dedwen and Sesostris III at Semna * The granite columns from the Faras Cathedral * A part of the paintings of the Faras Cathedral; the other part is in the National Museum of
Warsaw Warsaw, officially the Capital City of Warsaw, is the capital and List of cities and towns in Poland, largest city of Poland. The metropolis stands on the Vistula, River Vistula in east-central Poland. Its population is officially estimated at ...
. The Temple of Ptah at Gerf Hussein had its free-standing section reconstructed at New Kalabsha, alongside the Temple of Kalabsha, Beit el-Wali, and the Kiosk of Qertassi. The remaining archaeological sites, including the Buhen fort and the cemetery of Fadrus have been flooded by Lake Nasser.


Loss of sediments

Before the construction of the High Dam, the Nile deposited
sediment Sediment is a solid material that is transported to a new location where it is deposited. It occurs naturally and, through the processes of weathering and erosion, is broken down and subsequently sediment transport, transported by the action of ...
s of various particle size – consisting of fine sand, silt and
clay Clay is a type of fine-grained natural soil material containing clay minerals (hydrous aluminium phyllosilicates, e.g. kaolinite, ). Most pure clay minerals are white or light-coloured, but natural clays show a variety of colours from impuriti ...
– on fields in Upper Egypt through its annual flood, contributing to soil fertility. However, the nutrient value of the sediment has often been overestimated. 88 percent of the sediment was carried to the sea before the construction of the High Dam. The nutrient value added to the land by the sediment was only 6,000 tons of potash, 7,000 tons of phosphorus pentoxide and 17,000 tons of nitrogen. These amounts are insignificant compared to what is needed to reach the yields achieved today in Egypt's irrigation. Also, the annual spread of sediment due to the Nile floods occurred along the banks of the Nile. Areas far from the river which never received the Nile floods before are now being irrigated. A more serious issue of trapping of sediment by the dam is that it has increased coastline erosion surrounding the Nile Delta. There is a lack of reliable statistics.


Waterlogging and increase in soil salinity

Before the construction of the High Dam, groundwater levels in the Nile Valley fluctuated per year with the water level of the Nile. During summer when evaporation was highest, the groundwater level was too deep to allow salts dissolved in the water to be pulled to the surface through
capillary action Capillary action (sometimes called capillarity, capillary motion, capillary rise, capillary effect, or wicking) is the process of a liquid flowing in a narrow space without the assistance of external forces like Gravitation, gravity. The effe ...
. With the disappearance of the annual flood and heavy year-round irrigation, groundwater levels remained high with little fluctuation leading to waterlogging. Soil salinity also increased because the distance between the surface and the groundwater table was small enough (1–2 m depending on soil conditions and temperature) to allow water to be pulled up by evaporation so that the relatively small concentrations of salt in the groundwater accumulated on the soil surface over the years. Since most of the farmland did not have proper subsurface drainage to lower the groundwater table, salinization gradually affected crop yields. Drainage through sub-surface drains and drainage channels is essential to prevent a deterioration of crop yields from soil salinization and waterlogging. By 2003, more than 2 million hectares have been equipped with a subsurface drainage system at a cost from 1973 to 2002 of about $3.1 billion.


Health

Contrary to many predictions made prior to the Aswan High Dam construction and publications that followed, that the prevalence of schistosomiasis (bilharzia) — a tropical disease spread by contact with
fresh water Fresh water or freshwater is any naturally occurring liquid or frozen water containing low concentrations of dissolved salt (chemistry), salts and other total dissolved solids. The term excludes seawater and brackish water, but it does include ...
contaminated with parasitic flatworms — would increase, it did not. This assumption did not take into account the extent of perennial
irrigation Irrigation (also referred to as watering of plants) is the practice of applying controlled amounts of water to land to help grow crops, landscape plants, and lawns. Irrigation has been a key aspect of agriculture for over 5,000 years and has bee ...
that was already present throughout Egypt decades before the high dam closure. By the 1950s only a small proportion of Upper Egypt had not been converted from basin (low transmission) to perennial (high transmission) irrigation. Expansion of perennial irrigation systems in Egypt did not depend on the high dam. In fact, within 15 years of the high dam closure there was solid evidence that bilharzia was declining in Upper Egypt. ''S. haematobium'' has since disappeared altogether. Suggested reasons for this include improvements in irrigation practice. In the Nile Delta, schistosomiasis had been highly endemic, with prevalence in the villages 50% or higher for almost a century before. This was a consequence of the conversion of the Delta to perennial irrigation to grow long staple cotton by the British. This has changed. Large-scale treatment programmes in the 1990s using single-dose oral medication contributed greatly to reducing the prevalence and severity of ''S. mansoni'' in the Delta.


Other effects

Sediment deposited in the reservoir is lowering the water storage capacity of Lake Nasser. The reservoir storage capacity is 162 km3, including 31 km3 dead storage at the bottom of the lake below above sea level, 90 km3 live storage, and 41 km3 of storage for high flood waters above above sea level. The annual sediment load of the Nile is about 134 million tons. This means that the dead storage volume would be filled up after 300–500 years if the sediment accumulated at the same rate throughout the area of the lake. Obviously sediment accumulates much faster at the upper reaches of the lake, where sedimentation has already affected the live storage zone. Before the construction of the High Dam, the of irrigation and drainage canals in Egypt had to be dredged regularly to remove sediments. After construction of the dam, aquatic weeds grew much faster in the clearer water, helped by fertilizer residues. The total length of the infested waterways was about in the mid-1990s. Weeds have been gradually brought under control by manual, mechanical and biological methods. Mediterranean fishing and brackish water lake fishery declined after the dam was finished because nutrients that flowed down the Nile to the Mediterranean were trapped behind the dam. For example, the sardine catch off the Egyptian coast declined from 18,000 tons in 1962 to a mere 460 tons in 1968, but then gradually recovered to 8,590 tons in 1992. A scientific article in the mid-1990s noted that "the mismatch between low primary productivity and relatively high levels of fish production in the region still presents a puzzle to scientists." A concern before the construction of the High Dam had been the potential drop in river-bed level downstream of the Dam as the result of erosion caused by the flow of sediment-free water. Estimates by various national and international experts put this drop at between and . However, the actual drop has been measured at , much less than expected. The red-brick construction industry, which consisted of hundreds of factories that used Nile sediment deposits along the river, has also been negatively affected. Deprived of sediment, they started using the older alluvium of otherwise arable land taking out of production up to annually, with an estimated destroyed by 1984 when the government prohibited, "with only modest success," further excavation. According to one source, bricks are now being made from new techniques which use a sand-clay mixture and it has been argued that the mud-based brick industry would have suffered even if the dam had not been built. Because of the lower turbidity of the water sunlight penetrates deeper in the Nile water. Because of this and the increased presence of nutrients from fertilizers in the water, more algae grow in the Nile. This in turn increases the costs of drinking water treatment. Apparently few experts had expected that water quality in the Nile would actually decrease because of the High Dam.


See also

* Closure of the Suez Canal (1967–1975) * Energy in Egypt * Egyptian Public Works * List of conventional hydroelectric power stations * List of largest dams * List of power stations in Egypt * Water politics in the Nile Basin


References


External links


View the official opening of the Aswan Dam in 1971

Aswan Dam
Sixth biggest dam
LIFE Magazine Feb. 12, 1971
Overview of problems created by Aswan Dam {{Authority control Dams completed in 1970 Energy infrastructure completed in 1967 Energy infrastructure completed in 1971 Aswan Buildings and structures in Aswan Governorate Dams on the Nile Rock-filled dams Gravity dams Dams in Egypt Hydroelectric power stations in Egypt Environment of Egypt Lake Nasser Nubia Irrigation in Egypt River regulation in Egypt Egypt–Soviet Union relations Egypt–United States relations 1970 establishments in Egypt Energy infrastructure completed in 1902 1902 establishments in Egypt Soviet foreign aid Tourist attractions in Egypt Forced migration 20th-century architecture in Egypt