AswanAswan, formerly spelled Assuan, is a city in the south of Egypt, the capital of the Aswan Governorate....
(Assuan)
EgyptEgypt , officially the Arab Republic of Egypt, is a country mainly in North Africa, with the Sinai Peninsula forming a land bridge in Western Asia...
is the city located near the first
cataractThe cataracts of the Nile are shallow stretches of the river between Aswan and Khartoum where the water's surface is broken by numerous small boulders and stones protruding from the river bed, as well as many small rocky islets...
of the
NileThe Nile is a major north-flowing river in Africa, generally regarded as the longest river in the world....
, which presented the first obstacle from the
Mediterranean SeaThe Mediterranean Sea is a sea connected to the Atlantic Ocean surrounded by the Mediterranean region and almost completely enclosed by land: on the north by Anatolia and Europe, on the south by Africa, and on the east by the Levant. The sea is technically a part of the Atlantic Ocean, although it...
for boats sailing on the river since antiquity. Two
damA dam is a barrier that impounds water or underground streams. Dams generally serve the primary purpose of retaining water, while other structures such as floodgates or levees are used to manage or prevent water flow into specific land regions...
s now straddle the Nile river at this location: the newer and larger
Aswan High Dam , completed in 1970, and the earlier
Old Aswan Dam or
Aswan Low Dam, first completed in 1902. The aim of these water projects were to regulate river flooding, provide storage of water for
agricultureAgriculture is the production of food and goods through farming and forestry. Agriculture was the key development that led to the rise of human civilization, with the husbandry of domesticated animals and plants creating food surpluses that enabled the development of more densely populated and...
, and later, to generate
electricityElectricity is a general term that encompasses a variety of phenomena resulting from the presence and flow of electric charge...
. The former cataract and the Old Aswan Dam are about up-river and south southeast of Cairo. The new Aswan High Dam is a further upriver from the older dam.
Before the dams were built, the
River NileThe Nile is a major north-flowing river in Africa, generally regarded as the longest river in the world....
floodA flood is an overflow or accumulation of an expanse of water that submerges land. In the sense of "flowing water", the word may also be applied to the inflow of the tide....
ed each year during summer, as water flowed down the valley from its
East AfricaEast Africa or Eastern Africa is the easterly region of the African continent, variably defined by geography or geopolitics. In the UN scheme of geographic regions, 19 territories constitute Eastern Africa:...
n
drainage basinA drainage basin is an extent of land where water from rain or snow melt drains downhill into a body of water, such as a river, lake, reservoir, estuary, wetland, sea or ocean...
. These floods brought high water, plus natural
nutrientA nutrient is a chemical that an organism needs to live and grow or a substance used in an organism's metabolism which must be taken in from its environment. Nutrients are the substances that enrich the body. They build and repair tissues, give heat and energy, and regulate body processes...
s and
mineralA mineral is a naturally occurring solid formed through geological processes that has a characteristic chemical composition, a highly ordered atomic structure, and specific physical properties. A rock, by comparison, is an aggregate of minerals and/or mineraloids, and need not have a specific...
s that continuously enriched the fertile
soilSoil is a natural body consisting of layers of mineral constituents of variable thicknesses, which differ from the parent materials in their morphological, physical, chemical, and mineralogical characteristics. It is composed of particles of broken rock that have been altered by chemical and...
along the river and made the Nile valley ideal for farming, as it had since ancient times. As Egypt's population grew and conditions changed, there came a need to control the flood waters to both protect and support farmland and economically important cotton fields. In high-water years, the whole
cropA crop is the annual or season's yield of any plant that is grown in significant quantities to be harvested as food, as livestock fodder, fuel, or for any other economic purpose. This category includes crop species as well as agricultural techniques related to cropping.There are many types of crops...
might be wiped out, while in low-water years widespread
droughtA drought is an extended period of months or years when a region notes a deficiency in its water supply. Generally, this occurs when a region receives consistently below average precipitation. It can have a substantial impact on the ecosystem and agriculture of the affected region...
and
famineA famine is a widespread scarcity of food that may apply to any faunal species, which phenomenon is usually accompanied by regional malnutrition, starvation, epidemic, and increased mortality...
had sometimes occurred. With the reservoir storage provided by these dams, the floods could be lessened, and the water could be stored for later release.
Construction history
The earliest attempt of building a dam in Aswan dates back to the 1000s, when the
IraqIraq , officially the Republic of Iraq , also known as Mesopotamia, is a country in Western Asia spanning most of the northwestern end of the Zagros mountain range, the eastern part of the Syrian Desert and the northern part of the Arabian Desert.Iraq shares borders with Jordan to the west, Syria...
i polymath and engineer Ibn al-Haytham (known as
Alhazen in the West) was summoned to Egypt by the Fatimid Caliph,
Al-Hakim bi-Amr AllahAbu ‘Ali Mansur Tāriqu l-Ḥākim, called Al-Hakim bi Amr al-Lāh , was the sixth Fatimid caliph and 16th Ismaili imam ....
, to regulate the
flooding of the NileFlooding of the Nile is an important cycle in Egypt. It is celebrated by Egyptians as an annual holiday for two weeks starting August 15, known as Wafaa El-Nil. It is also celebrated in the Coptic Church by ceremonially throwing a martyr's relic into the river...
, a task requiring an early attempt at an Aswan Dam. After his
field workField work is a general descriptive term for the collection of raw data. The term is mainly used in the natural and social sciences studies, such as in anthropology, archaeology, biology, ecology, environmental science, ethnomusicology, geography,geology, geophysics, linguistics,paleontology, and...
made him aware of the impracticality of this scheme, and fearing the caliph's anger, he
feigned madnessFeigned madness a term used in popular culture to describe the assumption of a mental condition or illness by a person for purposes of evasion or deceit.Such an act can also be used to divert suspicion, perhaps in advance of an act of revenge....
. He was kept under
house arrestIn justice and law, house arrest is a measure by which a person is confined by the authorities to his or her residence. Travel is usually restricted, if allowed at all...
from 1011 until al-Hakim's death in 1021, during which time he wrote his influential
Book of OpticsThe Book of Optics was a seven-volume treatise on optics, physics, mathematics, anatomy and psychology written by the Iraqi Muslim scientist, Ibn al-Haytham , from 1011 to 1021, when he was under house arrest in Cairo, Egypt.The book...
.
Following their 1882, invasion and occupation of Egypt, the British began construction of the first dam across the Nile in 1898. Construction lasted until 1902, and it was opened on 10 December 1902, by HRH the
Duke of Connaught and StrathearnThe title Duke of Connaught and Strathearn was granted by Queen Victoria of the United Kingdom of Great Britain and Ireland to her third son, Prince Arthur....
. The project was designed by Sir
William WillcocksSir William Willcocks KCMG was a British civil engineer. He is remembered as a renowned irrigation engineer, having proposed the first Aswan Dam and undertaken major projects of irrigation in South Africa and Turkey.A graduate of the Thomason College of Civil Engineeering, Roorkee 1872 batch...
and involved several eminent engineers of the time, including Sir
Benjamin BakerSir Benjamin Baker KCB KCMG FRS was an eminent British civil engineer who worked in mid to late Victorian era. He helped develop the early underground railways in London with Sir John Fowler, but he is best known for his work on the Forth Bridge...
and Sir
John AirdSir John Aird, 1st Baronet was a notable English civil engineering contractor of the late 19th and early 20th centuries...
, whose firm,
John Aird & Co.John Aird & Co. was once a leading British civil engineering business based in London.-Early history:The company was founded in 1848 by John Aird with the objective of laying mains for gas and water companies in London....
, was the main contractor. A gravity dam, it was 1,900 m long and 54 m high. The initial design was soon found to be inadequate and the height of the dam was raised in two phases, 1907-1912 and 1929-1933.
When the dam almost overflowed in 1946 it was decided that rather than raise the dam a third time, a second dam would be built 6 km upriver (about 4 miles). Proper planning began in 1954 just after the Egyptian Revolution led by the Free Officers, of whom
NasserGamal Abdel Nasser was the second President of Egypt from 1956 until his death in 1970. He led the Egyptian Revolution of 1952, which removed King Farouk I and heralded a new period of industrialization in Egypt, together with a profound advancement of Arab nationalism, including a short-lived...
was to become leader.
Aswan High Dam in International Perspective
In 1955 Nasser was trying to portray himself as leader of Arab nationalism, in opposition to Hashemite Iraq, especially following the Baghdad Pact of 1955. At this time the US was much more concerned with the possibility of communism spreading to the Middle East than protecting Israel, and saw Nasser as a natural leader of an anti-communist Arab league. The US and Britain offered to help finance construction with a loan of US$270 million in return for Nasser's leadership on resolving the Arab-Israeli conflict. Nasser presented himself as a tactical neutralist, and sought to play off US and Soviet concerns to Egyptian and Arab benefit.
After Israel soundly defeated Egyptian forces in Gaza, Nasser realised that he could not legitimately portray himself as the leader of pan-Arab nationalism if Israel could push him around militarily. He looked to quickly modernise his military, and he turned first to the US.
John Foster DullesJohn Foster Dulles served as U.S. Secretary of State under President Dwight D. Eisenhower from 1953 to 1959. He was a significant figure in the early Cold War era, advocating an aggressive stance against communism around the world...
and US President Dwight Eisenhower told Nasser that the US would supply him with weapons only if they could send military personnel to supervise the training and use of the weapons. Nasser did not like these conditions and looked to the Soviet Union. Dulles believed that Nasser was only bluffing, and that the USSR would not aid Nasser. But the USSR promised Nasser a quantity of arms in exchange for a deferred payment of Egyptian grain and cotton. Instead of retaliating against Nasser for turning to the Soviets, Dulles sought to improve relations with him. This explains the US/British offer of December 1955.
Though the Czechoslovak arms deal actually increased US willingness to invest in Aswan, the British cited the deal as a reason for withdrawing their funding. What angered Dulles much more was Nasser’s recognition of communist China, which was in direct conflict with Dulles's policy of
containmentContainment was a United States policy using military, economic, and diplomatic strategies to temper the spread of Communism, enhance America’s security and influence abroad, and prevent a "domino effect". A component of the Cold War, the policy was a response to a series of moves by the Soviet...
. There are several other reasons why the US decided to withdraw the offer of funding. Dulles believed that the Soviet Union would not actually make good on its promise to help the Egyptians. He was also irritated by Nasser’s neutrality and attempts to play both sides of the Cold War. Actual NATO allies in the Middle East, like Turkey and Iraq, were irritated that a persistently neutral country like Egypt was being offered so much aid.
Timeline of US-USSR power-plays over Aswan
September 27 1955: Nasser announces arms deal with Czechoslovakia, with Czechoslovakia acting as a middleman for the USSR.
December 1955: US and Britain pledge $56 and $14 million respectively towards construction of dam.
May 1956: Nasser recognizes communist China, which is in direct conflict with Dulles’s policy of containment.
June 1956: Soviets offer Nasser $1,120,000,000 at 2% interest for the construction of the dam.
July 19 1956: The United States State Department's announces that it deemed American financial assistance for the High Dam "not feasible in present circumstances."
July 26 1956: Nasser nationalizes the Suez Canal. The Suez War breaks out, and Egypt is invaded by France, the UK, and Israel.
In 1958, the
Soviet UnionThe Union of Soviet Socialist Republics was a constitutionally socialist state that existed in Eurasia from 1922 to 1991. The name is a translation of the , tr. Soyuz Sovetskikh Sotsialisticheskikh Respublik, abbreviated СССР, SSSR. The common short name is Soviet Union, from , Sovetskiy Soyuz...
stepped in and funded the dam project. The Soviets also provided technicians and heavy machinery. The enormous rock and clay dam was designed by the Soviet Hydroproject Institute.
Construction began in 1960. The High Dam,
as-Sad al-'Aali, an
embankment damAn embankment dam is a massive artificial water barrier. It is typically created by the emplacement and compaction of a complex semi-plastic mound of various compositions of soil, sand, clay and/or rock. It has a semi-permanent waterproof natural covering for its surface, and a dense, waterproof...
, was completed on 21 July 1970, so therefore took 10 years to build with the first stage finished in 1964. The reservoir began filling in 1964 while the dam was still under construction and first reached capacity in 1976. The reservoir raised concerns from archaeologists and a rescue operation was begun in 1960 under
UNESCOThe United Nations Educational, Scientific and Cultural Organization is a specialized agency of the United Nations established on 16 November 1945...
. Sites were to be surveyed and excavated and 24 major monuments were moved to safer locations (see
Abu SimbelAbu Simbel is an archaeological site comprising two massive rock temples in Nubia, southern Egypt on the western bank of Lake Nasser about 290 km southwest of Aswan...
) or granted to countries that helped with the works (such as the
Debod templeThe Temple of Debod is an ancient Egyptian temple which was rebuilt in Madrid, Spain.The temple was built originally 15 km south of Aswan in southern Egypt very close to the first cataract of the Nile and to the great religious center dedicated to the goddess Isis, in Philae...
in Madrid and the
Temple of DendurThe Temple of Dendur is a Nubian temple that was built by the Roman governor of Egypt, Petronius, around 15 BC and dedicated to Isis, Osiris, as well as two deified sons of a local Nubian chieftain, Pediese and Pihor...
in New York).
On the Egyptian side, the project was led by
Osman Ahmed OsmanOsman Ahmed Osman was a famous and influential Egyptian engineer, contractor, entrepreneur, and politician. Known commonly as el-mo'alim , Osman founded the Arab Contractors and led the Egyptian effort to build the Aswan Dam...
's Arab Contractors. The relatively young Osman underbid his only competitor by one-half .
Specifications
The Aswan High Dam is 3,830 metres long, 980 metres wide at the base, 40 metres wide at the crest and 111 metres tall. It contains 43 million cubic metres of material. At maximum, 11,000 cubic metres of water can pass through the dam every second. There are further emergency spillways for an extra 5000 cubic metres per second and the Toshka Canal links the reservoir to the Toshka Depression. The reservoir, named
Lake NasserLake Nasser is a vast reservoir in southern Egypt and northern Sudan. Strictly, "Lake Nasser" refers only to the much larger portion of the lake that is in Egyptian territory , with the Sudanese preferring to call their smaller body of water Lake Nubia...
, is 550 km long and 35 km at its widest with a surface area of 5,250 square kilometres. It holds 111 cubic kilometres of water.
Benefits
Periodic floods and droughts, known since Biblical times (Gen 41:35-36), caused devastating effect on the population in the Nile Delta. The dam mitigated the effects of these dangerous floods such as in 1964 and 1973 and of threatening droughts in 1972-73 and the drought of 1983-84 that devastated East Africa and Somalia.
A new fishing industry has been created around Lake Nasser, though it is struggling due to its distance from any significant markets.The dam powers twelve generators each rated at 175 megawatts, producing a hydroelectric output of 2.1 gigawatts.
Power generation began in 1967. When the dam first reached peak output it produced around half of Egypt's entire electricity production (about 15% by 1998) and allowed for the connection of most Egyptian villages to use electricity for the first time.
Environmental and cultural problems
Damming the Nile has caused a number of environmental and cultural problems. It flooded much of lower
NubiaNubia is the region in the south of Egypt, along the Nile and in northern Sudan. Most of Nubia is situated in Sudan with about a quarter of its territory in Egypt...
and over 60,000 people were displaced. Lake Nasser flooded valuable archaeological sites such as the
BuhenBuhen was an ancient Egyptian settlement situated below the Second Cataract. It is well known for its fortress, probably constructed during the rule of Senusret III, around the year 1860 BC . The site may have been first established as an outpost in Nubia during the reign of Sneferu...
fort. The valuable silt which the Nile deposited ashore in the yearly floods and made the Nile floodplain fertile is now held behind the dam. Silt deposited in the reservoir is lowering the water storage capacity of Lake Nasser. Poor irrigation practices are waterlogging soils and bringing salt to the surface. Mediterranean fishing declined after the dam was finished because nutrients that used to flow down the Nile to the Mediterranean were trapped behind the dam.
There is some
erosionErosion is a gravity driven process that moves solids in the natural environment or their source and deposits them elsewhere...
of farmland down-river as the river replenishes its sediment load. Erosion of coastline barriers due to lack of new sediments from floods will eventually cause loss of the brackish water lake fishery that is currently the largest source of fish for Egypt, and the subsidence of the
Nile DeltaThe Nile Delta is the delta formed in Northern Egypt where the Nile River spreads out and drains into the Mediterranean Sea. It is one of the world's largest river deltas—from Alexandria in the west to Port Said in the east, it covers some 240 km of Mediterranean coastline—and is a rich...
will lead to inundation of the northern portion of the
deltaA delta is a landform that is created at the mouth of a river where that river flows into an ocean, sea, estuary, lake, reservoir, flat arid area, or another river. Deltas are formed from the deposition of the sediment carried by the river as the flow leaves the mouth of the river...
with seawater, in areas which are now used for rice crops. The delta itself, no longer renewed by Nile silt, has lost much of its fertility. The red-brick construction industry, which used delta mud, is also severely affected. There is significant erosion of coastlines (due to lack of sand, which was once brought by the Nile) all along the eastern Mediterranean.
As salt water stagnates and evaporates it leaves behind salt crystals on the soil, causing salinisation and decreased yield. Furthermore, the standing water is a breeding ground for snails carrying the parasite bilharzia, the second most socioeconimically negative parasite, second only to
malariaMalaria is a vector-borne infectious disease caused by a eukaryotic protist of the genus Plasmodium. It is widespread in tropical and subtropical regions, including parts of the Americas, Asia, and Africa. Each year, there are approximately 350–500 million cases of malaria, killing between one and...
.
The increased use of artificial
fertilizerFertilizers are chemical compounds applied to promote plant and fruit growth. Fertilizers are usually applied either through the soil or by foliar feeding...
s in farmland below the dam has caused chemical pollution which the traditional river silt did not. Indifferent irrigation control has also caused some farmland to be damaged by waterlogging and increased
salinitySalinity is the saltiness or dissolved salt content of a body of water. It is a general term used to describe the levels of different salts such as sodium chloride, magnesium and calcium sulfates, and bicarbonates...
, a problem complicated by the reduced flow of the river, which allows salt water to encroach further into the
deltaA delta is a landform that is created at the mouth of a river where that river flows into an ocean, sea, estuary, lake, reservoir, flat arid area, or another river. Deltas are formed from the deposition of the sediment carried by the river as the flow leaves the mouth of the river...
.
The Aswan Dam tends to increase the salinity of the Mediterranean Sea, and this affects the Mediterranean's outflow current into the Atlantic Ocean (see
Strait of GibraltarThe Strait of Gibraltar is a narrow strait that connects the Atlantic Ocean to the Mediterranean Sea and separates Spain from Morocco...
). This current can be traced thousands of kilometers into the Atlantic.
Due to the Aswan Dam inhibiting the natural fluctuations in water height, i.e. floods, the bilharzia disease has flourished causing great expense to the Egyptian economy and people. The battle with the disease continues.
Irrigation for agriculture
Due to the absence of appreciable rainfall, Egypt's agriculture depends entirely on
irrigationIrrigation is an artificial application of water to the soil. It is usually used to assist in growing crops in dry areas and during periods of inadequate rainfall...
. With irrigation, two crops per year can be produced, except for sugar cane that has a growing period of almost one year. The high dam at Aswan releases on average 55 billion m³ water per year of which some 46 billion m³ are diverted into the irrigation canals. In the Nile valley and delta, almost 8 million
feddanA feddan is a unit of area. It is used in Egypt, Sudan, and Syria. The feddan is not an SI unit and in Arabic, the word means 'a yoke of oxen': implying the area of ground that could be tilled by them in a certain time...
(1 feddan is 1.038 acre or 4200.835 m
2) benefit from these waters producing on average 1.8 crops per year. The annual crop consumptive use of water is about 38 billion m³. Hence, the overall irrigation efficiency is 38/46 = 0.82 or 82%. Compared to the efficiency elsewhere in the world this is a high value. The field irrigation efficiencies are much less, but the losses are re-used downstream. This continuous re-use accounts for the high overall efficiency. The equal distribution of irrigation water over the branch canals taking off from the main irrigation canals leaves much to be desired.
| Branch canal |
Water delivery in m³/feddan* |
| Kafret Nasser |
4700 |
| Beni Magdul |
3500 |
| El Mansuria |
3300 |
| El Hammami upstream |
2800 |
| El Hammami downstream |
1800 |
| El Shimi |
1200 |
* Period 1 March to 31 July. 1 feddan is about 1 acre or 0.42 ha. Data from Egyptian Water Use Management Project (EWUP)
The salt concentration of the water in the Aswan reservoir is about 0.25 kg/m³. This is very "sweet" water. At an annual inflow of 55 billion m³, the annual salt import reaches 14 million ton. The average salt concentration of the drainage water evacuated into the sea and the coastal lakes is 2.7 kg/m³ (Egyptian Drainage Research Institute, yearbook 1995/1996). At an annual discharge of 10 billion m³ (not counting the 2 billion m³ of salt intrusion from the sea and the lakes, see figure "Water balances"), the annual salt export reaches 27 million ton. In 1995, the salt export was higher than the import, and Egypt's agricultural lands were
desalinizingIn agriculture, leaching refers to the loss of water-soluble plant nutrients from the soil, due to rain and irrigation. Soil structure, crop planting, type and application rates of fertilizers, and other factors are taken into account to avoid excessive nutrient loss.
Leaching may also refer to...
. Part of this could be due to the large number of
subsurface drainageAn agricultural drainage system is a system by which the water level on or in the soil is controlled to enhance agricultural crop production.-Classification:...
projects executed in the last decades to control the
control the water tableWatertable control is the practice of controlling the water table in agricultural land by subsurface drainage with proper criteria to improve the crop production.- Description/Definitions :...
and soil salinity.
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