Why the Aswan Dam is interesting to tourists and engineers - technical features and photos. Aswan Dam in Egypt

1) I dreamed of seeing the Aswan Dam (السد العالي‎) since I was in grades 10-11, when I read about it in General History lessons from Nikita Zagladin’s textbook. Fortunately, studying at Cairo University gave me the opportunity to get there with fellow students from RUDN University and Kazan University. For me, the fact is that it is precisely to the south of the dam that crocodiles begin to live, which did not survive to the north for 960 km downstream of the Nile before it flows into the Mediterranean Sea.

2) The Nile originates at the lake. Victoria in the south of the African continent. Flowing north to Mediterranean Sea, the river divides it into western and eastern parts, crossing Uganda, Ethiopia, Sudan and ending with Egypt on its way. Each of these states has its own interests in using it water resources. Without a reservoir, the Nile overflowed its banks every year during the summer, overflowing with the flow of water from eastern Africa. These floods carried fertile silt and minerals that made the soil around the Nile fertile and ideal for Agriculture. As the population along the river's banks grew, there was a need to control the flow of water to protect farmland and cotton fields. The average annual flow of the Nile in the area of Sudan and Egypt is estimated at 84 billion cubic meters. The average annual river flow is subject to significant fluctuations. The decrease in runoff in some years reaches 45 billion cubic meters, which leads to droughts, an increase to 150 billion cubic meters. causes floods. In a high-water year, entire fields could be completely washed away, while in a low-water year, famine due to drought was widespread. The purpose of this water project was to prevent floods, provide Egypt with electricity, and create a network of irrigation canals for agriculture.

3) Help for engineers.
A special feature of the hydroelectric station is the design of the spillways with the water exiting not under the water level of the downstream canal, but into the atmosphere with a jet discharge at a distance of 120-150 meters from the hydroelectric power station building. The water flow rate released by 12 spillways reaches 5000 m³ per second. The energy of the flow is extinguished due to the rise of the jet 30 m above the water level of the tailwater and subsequent fall into a channel about 20 m deep. For the first time in world practice, such a solution was used during the construction of the Kuibyshev hydroelectric station.
The Aswan High Dam consists of 3 sections. The right-bank and left-bank sections of the dam, 30 m high, have a rocky base, the channel section is 550 m long, 111 m high, and has a sandy base. The thickness of the sand at the base is 130 meters. The dam was built in an existing reservoir 35 meters deep without damming or draining the foundation. The dam has a flattened profile and is built from local materials. The core and rim of the dam are made of so-called Aswan clay.

7) The day of the official opening of construction is January 9, 1960. On this day, the President of Egypt, pressing the red button on the explosive device remote control, exploded rock in the pit of future structures. On May 15, 1964, the Nile was blocked. On this day construction site Nikita Sergeevich Khrushchev, Algerian President Ferhat Abbas and Iraqi President Abdul Salam Aref visited. The Upper Dam was completed on July 21, 1970, but the reservoir began to fill in 1964, when the first stage of construction of the dam was completed.

8) The grand opening and commissioning of the Aswan hydropower complex took place on January 15, 1971 with the participation of the President of the UAR Anwar Sadat, who cut the ribbon in the blue arch on the crest of the dam, and the Chairman of the Presidium of the Supreme Council of the USSR N.V. Podgorny.
The history of this grandiose hydroelectric complex began in the Ukrainian city of Zaporozhye. Soviet contractors of the Egyptian project built a miniature of the future Aswan Dam (50 times smaller) at the Pravoberezhny quarry. For two years, the Dneprostroy company carried out all necessary work, upon completion of which the necessary tests took place and scientists chose a successful hydraulic option. More than 50 years have passed since that time, however, even now we can see the experimental construction of a dam on the territory of the Right Bank quarry of Zaporozhye.

9) After the construction of the Aswan hydroelectric complex, they were prevented Negative consequences the floods of 1964 and 1973, and the droughts of 1972-1973 and 1983-1984. A significant number of fisheries have developed around Lake Nasser. At the time of the launch of the last unit in 1967, the hydroelectric complex generated more than half of all electricity in the country. 15% in 1988.

10)

11) Russian students in Aswan before the forced march to the Aswan Dam.

12) How did the day begin then? Having visited Philae Island, we all realized that the Aswan Dam is 11 km away. At first we wanted to walk, then a taxi driver picked us up and took us to the beginning of the waterworks. The picture shows an old English dam and beyond that the Nile River.

13) Hydroelectric power station Big Dam.

14) So, Firuza.

15) "Smirnova Margarita Yuryevna." Rita, if you read the text, you will immediately understand where it all comes from.

16) Arslan.

17) In 1966, the Egyptian Government allocated money to hold an international competition for the design of the Arab-Arab Friendship Monument Soviet peoples, so-called "The Flower of Aswan", installed in 1975. The five petals of the flower rise 75 meters high, and at a height of 46 meters they are united by a ring of an observation deck, where up to 6 people can stay at the same time and can be reached using an elevator.

On January 15, 1971, Egyptian President Anwar Sadat officially opened a dam across the Nile called. Work on its construction was carried out during the reign of President Abdel Nasser and continued for more than eleven years before the opening. Some geometric indicators of the Aswan Dam are as follows: the length of the dam is 3.8 kilometers, the height is 3 meters, the width at the base is 975 meters, and closer to the upper edge the width is already up to 40 meters.

The resource costs for the construction of the Aswan Dam are simply unimaginable. For this unique structure, such an amount of stone, clay, sand and concrete was used that would be enough to build 17 Cheops pyramids.

At the top of the dam there is a triumphal arch, under which a four-plane road passes. Also on the western edge there are four huge pointed monoliths.

One of the most important achievements of the Aswan Dam is that with its help it became possible to control the annual flood of the Nile. Since ancient times, the life of local residents directly depended on the Nile, or rather, its floods. In most cases, the Nile did not reach the households of local residents with its waters, but sometimes the Nile overflowed so much that it completely destroyed all crops, which meant a hungry year for the local population. The construction of the dam solved this problem and made it possible to fully utilize the vast territories.

But with the advantages of the dam came also disadvantages. The dam had a significant impact on environmental situation in this region, namely due to increased salt levels, changes in soil in adjacent areas, and as a result, significant changes in climate change in this region.

Go downstream another 60 kilometers and you will see the century-old Aswan Dam, the construction of which was completed back in 1902. At that time it was the greatest dam of its time, called El Sadd - as the Arabs called it.

Also amazing fact Sudan is the loss of 60,000 local residents during the construction process. As a result construction work local residents were simply forced to change their place of residence and leave these lands. Great amount priceless architectural structures were lost under the flows of the newly created reservoir. Only thanks to UNESCO's action were some of the most valuable ancient monuments saved. For example, the island of Philae was sunk under water, but despite this, the priceless temples were dismantled into numbered parts and moved to another place, located higher above sea level. Among those saved, the central one is a temple dedicated to the goddess Isis, some parts that date back to the first, second centuries BC. Also, 3 other temples moved to Kalabsha, to the eastern edge of the dam. But the most ambitious thing was the rescue of the monuments in Abu Simbel, located 282 km south of Aswan.

The winter resort, called Aswan itself, is blessed with a naturally ideal climate, with temperatures reaching 20 degrees during the skiing season. And in warm seasons, the temperature here can reach 50 degrees Celsius.

Experienced people can confidently say that the dates in Asaun are the most delicious in all of Egypt. Also here are most interesting places for walks, for example, the mausoleum of the Aga Khan, who died in 1957. It is also worth looking at the remains of the Coptic monastery, the ancient ruins of the island of Elephantine, located on the Nile, ancient Muslim cemetery, with its amazing burials, and other no less significant monuments of antiquity.

Aswan waterworks- the largest complex hydraulic system of structures in Egypt on the Nile River, near Aswan - a city on the first threshold of the Nile. ( Chief Engineer project - N. A. Malyshev) Two dams block the river at this place: the new “Aswan Upper Dam” (known as Aswan High Dam) (Arabic: السد العالي‎, As-Sad el-Aali) and the old “Aswan Dam” or “Aswan Lower Dam”.

The Nile originates at the lake. Victoria in the south of the African continent. Flowing north to the Mediterranean Sea, the river divides it into western and eastern parts, crossing Uganda, Ethiopia, Sudan and ending with Egypt on its way. Each of these states has its own interests in the use of its water resources. Without a reservoir, the Nile overflowed its banks every year during the summer, overflowing with the flow of water from eastern Africa. These floods carried fertile silt and minerals that made the soil around the Nile fertile and ideal for agriculture. As the population along the river's banks grew, there was a need to control the flow of water to protect farmland and cotton fields. The average annual flow of the Nile in the area of Sudan and Egypt is estimated at 84 billion cubic meters. The average annual river flow is subject to significant fluctuations. The decrease in runoff in some years reaches 45 billion cubic meters, which leads to droughts, an increase to 150 billion cubic meters. causes floods. In a high-water year, entire fields could be completely washed away, while in a low-water year, famine due to drought was widespread. The purpose of this water project was to prevent floods, provide Egypt with electricity, and create a network of irrigation canals for agriculture.

Design features

A special feature of the hydroelectric station is the design of the spillways with the water exiting not under the water level of the downstream canal, but into the atmosphere with a jet discharge at a distance of 120-150 meters from the hydroelectric power station building. The water flow rate released by 12 spillways reaches 5000 m³ per second. The energy of the flow is extinguished due to the rise of the jet 30 m above the water level of the tailwater and subsequent fall into a channel about 20 m deep. For the first time in world practice, such a solution was used during the construction of the Kuibyshev hydroelectric station

At the entrance section of the water intake, the tunnels are branched into two tiers. The lower tier, which is currently covered with a concrete plug, was used to pass water during the construction period. Along the upper tier, water is supplied to turbines and spillways. At the entrance of the tunnels there are two fast-falling wheeled gates with a height of 20 meters. Minimal amount turbines were determined largest diameter impeller, which can be carried along the Nile through existing locks. Based on this, six tunnels with a diameter of 15 meters were built - one for two turbines.

The Aswan High Dam consists of 3 sections. The right-bank and left-bank sections of the dam, 30 m high, have a rocky base, the channel section is 550 m long, 111 m high, and has a sandy base. The thickness of the sand at the base is 130 meters. The dam was built in an existing reservoir 35 meters deep without damming or draining the foundation. The dam has a flattened profile and is built from local materials. The core and bottom of the dam are made of so-called Aswan clays.

History of construction

To control the flow of the Nile, the first design for a dam below Aswan was first drawn up in the 11th century by Ibn al-Haytham. However, the project could not be implemented with technical means that time.

By the 1950s, several low-head dams had been built on the Nile. The highest of them is Aswan with a height of 53 m in the area of the first Nile threshold with a reservoir capacity of 5 billion cubic meters. was built by the British. Construction of the first dam began in 1899 and was completed in 1902. The project was designed by Sir William Willcox and involved several distinguished engineers, including Sir Benjamin Baker and Sir John Aird, whose firm, John Aird and Company, was the main contractor. The height of the constructed dam increased during the periods 1907-1912 and 1929-1933, but it only partially provided seasonal flow regulation.

After the 1952 revolution, three versions of a new dam were developed to regulate flow. The first was the expansion of the existing Aswan Dam, which was rejected because the topography of the banks did not allow the construction of a dam with a given reservoir elevation. The second and third options proposed placing the site of the new dam 6.5 and 40 km above the existing one, which, due to the terrain conditions, met the requirements for creating a long-term regulation reservoir. Based on geological conditions and transport connections, the option of locating the site 6.5 km above the Aswan Dam was chosen. But this site fell within the zone of an existing reservoir, which complicated the design of the dam and the technology of its construction.

By 1952, the English design and survey company "Alexander Gibb" (English) Russian). The Aswan High Dam project was developed. The maximum possible elevation of the reservoir's headwaters was determined, providing for the possibility of long-term regulation of the Nile flow. The reservoir's capacity was determined to be 157 billion cubic meters. of which about 30 billion cubic meters. 10 billion cubic meters were allocated for siltation. - for evaporation and filtration. This project involved the construction of drainage tunnels and transport tunnels total length 17 km. The drainage tunnels were to have a diameter of 14.6 m and a length of 2.1 km. These tunnels had to be lined with reinforced concrete lining. The hydroelectric power station building should have been underground type with tunnel water supply and drainage.

On December 4, 1954, an international committee submitted a report to the Egyptian government confirming the feasibility of the project. The construction cost was estimated at EGP 415 million, of which 35% was in foreign exchange for the purchase of construction and technological equipment. After this, the Egyptian government decided to immediately begin construction. The construction was supposed to be financed with the help of a loan from the International Bank for Reconstruction and Development. On July 17, 1956, the US State Department announced that the agreement to provide a loan to Egypt had been approved. The loan amount of $200 million was divided between the US (70%) and the UK (30%). The credit had to be provided by the International Bank in the form of a loan. However, two days later, on July 19, the bank withdrew its decision.

In March 1955, the first trade agreement was signed between the USSR and Egypt. The diplomatic mission in Cairo was transformed into an embassy, and on May 21, negotiations on supplies began in Moscow Soviet weapons which ended with the signing of an agreement. On July 26, 1956, President Abdel Nasser announced the nationalization of the Suez Canal, the annual revenues from the operation of which in the amount of $100 million would be used for the construction of the Aswan High Dam. England, France and Israel provoked a military conflict by occupying the canal with troops during the Suez crisis. In response, the Soviet Union sends warships into the Mediterranean Sea. Under pressure from the UN, USA and USSR, on November 6, 1956, a decision was made to stop the aggression and leave the canal in Egyptian hands. In the midst cold war in the fight for third world countries[ clarify].

On December 27, 1958, an agreement was signed between the USSR and Egypt on participation Soviet Union in the construction of the Aswan High Dam and the provision of credit for this construction. In accordance with this agreement, the Soviet Union provided a loan for 12 years with a rate of 2.5% per annum in the amount of 34.8 million Egyptian pounds for the supply of equipment and technical assistance for the first stage of construction, and on July 27, 1960 an additional agreement was concluded for the amount of 78.4 million pounds on the same terms to complete all work on the waterworks. The Hydroproject Institute was appointed as the general designer, N.A. Malyshev as the chief engineer, I.V. Komzin as the Chief Soviet expert, Georgy Aleksandrovich Radchenko as the deputy Chief expert, G.I. Sukharev as the deputy Chief expert for procurement, and G.I. Sukharev as the deputy Chief expert. for personnel - Vitaly Georgievich Morozov, head of the administrative group - Viktor Ivanovich Kulygin.

The Soviet project of the hydroelectric complex differed radically from the approved one. The site area was preserved, but the dam was placed 400 meters higher, and the diversion was adopted as a combined one. Its main part consists of inlet and outlet canals, and only a section of 315 meters is made in the form of six tunnels with a diameter of 15 meters. To create a diversion, an open rock excavation with a depth of up to 70 meters and a volume of about 10 million cubic meters was made. Stone from this excavation was used for filling the dam and for grading the construction site. Tunnels 315 meters long during the construction period, after blocking the riverbed, diverted water to the unfinished hydroelectric power station building, and during operation, water is supplied through them to turbines and spillways, also located in the hydroelectric power station building.

The construction management system began to take shape in 1952. At the beginning, several specialized committees were created. On October 19, 1955, the Aswan High Dam Authority was created under the Council of Ministers, headed by the Prime Minister. In 1958, the Higher Committee of the Aswan High Dam was formed. On August 16, 1961, the Ministry of the Aswan High Dam was established by republican decree. The Construction Department was established by the same decree. Moussa Arafa was appointed minister. In 1962, this post was taken by Aziz Mohammed Sidqi.

A Training Center was organized for all major construction and installation specialties, in which training was conducted according to the programs of the Soviet Union. Over the course of a year, 5 thousand people were trained at the training center. In total, about 100 thousand were trained during the construction period.

The day of the official opening of construction is January 9, 1960. On this day, the President of Egypt, pressing the red button on the explosive device remote control, exploded rock in the pit of future structures. On May 15, 1964, the Nile was blocked. On this day, the construction site was visited by Nikita Sergeevich Khrushchev, President of Algeria Ferhat Abbas and President of Iraq Abdul Salam Aref. The Upper Dam was completed on July 21, 1970, but the reservoir began to fill in 1964, when the first stage of construction of the dam was completed. The reservoir put many archaeological sites in danger of disappearing, so a rescue operation was undertaken under the auspices of UNESCO, as a result of which 24 major monuments were moved to more safe places or transferred to countries that helped with the work (Temple of Debod in Madrid, Temple of Dendur ( English) in New York, Temple of Tafis).

The grand opening and commissioning of the Aswan hydropower complex took place on January 15, 1971, with the participation of the President of the UAR Anwar Sadat, who cut the ribbon in the blue arch on the crest of the dam, and the Chairman of the Presidium of the Supreme Council of the USSR N.V. Podgorny.

In mid-May 2014, Egypt widely celebrated the 50th anniversary of the damming of the Nile, a key event in the joint construction of the high-rise Aswan Dam. A representative delegation of the Russian public took part in the celebration. Prime Minister Ibrahim Mahlyab spoke at the ceremonial meeting at the Cairo Opera, and Russian Ambassador Sergei Kirpichenko read out a welcoming telegram Russian President V.V. Putin to the interim President of Egypt Adly Mansour.

It turns out that the history of this grandiose hydroelectric complex began in the Ukrainian city of Zaporozhye. Soviet contractors of the Egyptian project built a miniature of the future Aswan Dam (50 times smaller) at the Pravoberezhny quarry. For two years, the Dneprostroy company carried out all the necessary work, upon completion of which the necessary tests took place and the scientists chose a successful hydraulic option. More than 50 years have passed since that time, however, even now we can see the experimental construction of a dam on the territory of the Right Bank quarry of Zaporozhye.

Economic significance

After the construction of the Aswan hydroelectric complex, the negative consequences of the floods of 1964 and 1973, as well as the droughts of 1972-1973 and 1983-1984, were prevented. A significant number of fisheries have developed around Lake Nasser. At the time of the launch of the last unit in 1967, the hydroelectric complex generated more than half of all electricity in the country. 15% in 1988. .

History of construction

The project of regulating the waters of the Nile by building a dam below Aswan was first drawn up in the 11th century by Ibn al-Haytham. However, the project could not be implemented with the technical means of that time. The British began construction of the first dam in 1899, finishing it in 1902. The project was designed by Sir William Willcox and involved several distinguished engineers, including Sir Benjamin Baker and Sir John Aird, whose firm, John Aird and Company, was the main contractor. The dam was an impressive structure 1,900 m long and 54 m high. The initial design, as it soon became clear, was inadequate, and the height of the dam was raised in two stages, 1907-1912 and 1929-1933.

Construction began in 1960. The Upper Dam was completed on July 21, 1970, however the reservoir began to fill already in 1964, when the first stage of construction of the dam was completed. The reservoir put many archaeological sites in danger of disappearing, so a rescue operation was undertaken under the auspices of UNESCO, as a result of which 24 major monuments were moved to safer places or transferred to countries that helped with the work (Temple of Debod in Madrid and Temple of Dendur in New York ).

Main characteristics of the waterworks

Panorama of Aswan High Dam

The Aswan High Dam is 3600 m long, 980 m wide at the base, 40 m wide at the crest and 111 m high, it consists of 43 million m³ soil materials. The maximum water flow through all culverts of the dam is 16,000 m³/s.

The Toshka Canal connects the reservoir with Lake Toshka. The reservoir, named Lake Nasser, has a length of 550 km and a maximum width of 35 km; Its surface area is 5250 km² and its total volume is 132 km³.

The capacity of twelve generators (each 175 MW) is 2.1 GW of electricity. When the hydroelectric power station reached its design output by 1967, it provided about half of all energy generated in Egypt.

Ecological problems

In addition to the benefits, however, the Nile seizure caused many environmental problems. Vast areas of lower Nubia were flooded, displacing more than 90,000 people. Lake Nasser flooded valuable archaeological sites. Fertile silt, which was washed annually during floods into the Nile floodplains, is now retained above the dam. Nowadays, silt is gradually raising the level of Lake Nasser. In addition, changes have occurred in the Mediterranean ecosystem - fish catches on the coast have decreased as nutrients have ceased to flow from the Nile.

There is some erosion of farmland downriver. Shoreline erosion, due to a lack of new sediment from floods, will eventually cause the loss of lake fisheries, which are currently Egypt's largest source of fish. Lowering of the Nile Delta will lead to an influx sea water to its northern part, where rice plantations are now located. The delta itself, no longer fertilized by Nile silt, lost its former fertility. The production of red brick, which uses delta clay, was also affected. There is significant erosion in the eastern Mediterranean coastlines due to a shortage of sand, which was previously brought by the Nile.

The need to use artificial fertilizers supplied by international corporations is also controversial because, unlike river silt, they cause chemical pollution. Inadequate irrigation control has resulted in some farmland being destroyed by flooding and increasing salinity. This problem is exacerbated by weakened river flows, causing salt water to intrude further into the delta.

Mediterranean fisheries were also affected by the dam's construction, as the marine ecosystem was heavily dependent on the rich flow of phosphates and silicates from the Nile. Mediterranean catches have dropped by almost half since the dam. Cases of schistosomiasis have increased as a large number of algae in Lake Nasser contributes to the proliferation of snails that carry this disease.

The Aswan Dam tends to increase the salinity of the Mediterranean Sea, thereby affecting the flow from the Mediterranean to Atlantic Ocean(see Strait of Gibraltar). This flow can be traced for thousands of kilometers in the Atlantic. Some people believe [ Who?] that this dam influence accelerates the processes that will lead to the next ice age.

At the end of the 1990s. Lake Nasser began to expand to the west and flood the Toshka lowland. To prevent this phenomenon, the Toshka Canal was built, allowing part of the Nile waters to be diverted to the western regions of the country.

The Sayano-Shushenskaya hydroelectric power station is the most powerful hydroelectric power station, and power station in general, in Russia. The grandiose structure is a dam, the height of which is 245 m, the width of the base is 110 m, and the length along the crest is 1066 m. The hydroelectric power station itself is located in the picturesque foothills of the Western Sayan.

Composition of hydroelectric power station structures:

concrete arch-gravity dam 245 m high, 1066 m long, 110 m wide at the base, 25 m wide at the crest. The dam includes a left-bank blind part 246.1 m long, a station part 331.8 m long, a spillway part 189 m long, 6 m and the right bank blind part 298.5 m long;

dam hydroelectric power station building;

coastal spillway.

The power of the hydroelectric power station is 6400 MW, the average annual output is 23.5 billion kWh. In 2006, due to a major summer flood, the power plant generated 26.8 billion kWh of electricity.

The hydroelectric power station building houses 10 radial-axial hydraulic units with a capacity of 640 MW each, operating at a design head of 194 m. The maximum static head on the dam is 220 m.

The hydroelectric dam is unique; only one other hydroelectric power station in Russia has a similar type of dam - the Gergebilskaya one, but it is much smaller.

Below the Sayano-Shushenskaya HPP is its counter-regulator - the Mainskaya HPP with a capacity of 321 MW, which is organizationally part of the Sayano-Shushenskaya HPP.

The hydroelectric dam forms the large Sayano-Shushenskoye reservoir with a total volume of 31.34 cubic meters. km (useful volume - 15.34 cubic km) and an area of 621 sq. km.

The constantly renewed water from the near-station part of the giant reservoir is superior in quality to that above the reservoir - it is not for nothing that trout, which cannot tolerate polluted water, successfully live in trout farms near the hydroelectric power station. When creating the reservoir, 35.6 thousand hectares of farmland were flooded and 2,717 buildings were moved. In the area of the reservoir there is the Sayano-Shushensky Biosphere Reserve.

The Sayano-Shushenskaya HPP was designed by the Lenhydroproekt Institute. On August 17, 2009, a major accident occurred at the Sayano-Shushenskaya hydroelectric power station, causing casualties.

Aswan Dam

The Aswan Dam is sometimes called the “pyramid of the 20th century” - in terms of its scale, the structure is not inferior to the grandiose creation of the ancients. Quite the contrary: 17 times more stone was used to build the dam than for the Cheops pyramid. And different countries of the world participated in the construction.

Without a reservoir, the Nile overflowed its banks every year during the summer, overflowing with the flow of water from eastern Africa. These floods carried fertile silt and minerals that made the soil around the Nile fertile and ideal for agriculture.

As the population along the river's banks grew, there was a need to control the flow of water to protect farmland and cotton fields. In a high-water year, entire fields could be completely washed away, while in a low-water year, famine due to drought was widespread. The purpose of the water project - the construction of a dam and reservoir - was to prevent floods, provide Egypt with electricity and create a network of irrigation canals for agriculture.

The British began building the first dam in 1899, finishing construction in 1902. The project was designed by Sir William Willcox and involved several distinguished engineers, including Sir Benjamin Baker and Sir John Aird, whose firm John Aird and Company was the main contractor. The dam was an impressive structure 1,900 m long and 54 m high. The initial design, as it soon became clear, was inadequate, and the height of the dam was raised in two stages, in 1907–1912 and 1929–1933.

Its characteristics were as follows: its length was 2.1 km, it had 179 culverts. On the left side of the dam there was a lock for transporting ships across the dam, and there was a power station nearby.

When in 1946 the water rose almost to the level of the dam, it was decided to build a second dam 6 km up the river. Work on its design began in 1952, immediately after the revolution. It was initially assumed that the United States and Great Britain would help finance construction by providing a loan of $270 million in exchange for Nasser's participation in resolving the Arab-Israeli conflict. However, in July 1956, both countries rescinded their proposal. As possible reasons This step is called a secret agreement on the supply of small arms with Czechoslovakia, which was part of the Eastern bloc, and Egypt's recognition of the PRC.

After Nassar nationalized the Suez Canal, intending to use tolls on passing ships to subsidize the Upper Dam project, Great Britain, France, and Israel provoked a military conflict by occupying the canal with troops during the Suez Crisis.

But under pressure from the UN, the USA and the USSR, they were forced to leave and leave the canal in Egyptian hands. At the height of the Cold War, in the struggle for the Third World, the Soviet Union in 1958 proposed technical assistance during the construction of the dam, and a third of the cost of the project was written off due to the loyalty of the Nasser regime to the USSR. The huge dam was designed by the Soviet institute "Gidroproekt".

Construction began in 1960. The Upper Dam was completed on July 21, 1970, but the reservoir began to fill in 1964, when the first stage of construction of the dam was completed. The reservoir put many archaeological sites in danger of disappearing, so a rescue operation was undertaken under the auspices of UNESCO, as a result of which 24 major monuments were moved to safer places or transferred to countries that helped with the work (Temple of Debod in Madrid and Temple of Dendur in New York).

The grand opening and commissioning of the Aswan hydropower complex took place on January 15, 1971, with the participation of the President of the United Arab Emirates Anwar Sadat, who cut the ribbon in the blue arch on the crest of the dam, and the Chairman of the Presidium of the Supreme Council of the USSR. V. Podgorny.

The Aswan Dam solved all the tasks assigned to it: to protect Egyptians living in the valley from floods and dry seasons by regulating the water level for many years. Irrigated land has increased by 30% - 800,000 hectares, old lands now produce not one harvest, but three. This became possible due to the fact that previously, when the land was flooded, residents planted crops there, and when the water receded from the Nile River, the crops were harvested, now the water has become constant and they can be planted all the time, without waiting for the river to flood again. But at the same time, people lost natural fertilizer - silt brought with the river flood; now they use imported fertilizers. In addition, the dam became the largest source of electricity, providing 2.1 million kW. Many villages had never had light in their homes before. During construction, thousands of Egyptians received a construction education, now many of them have become managers in government agencies and directors of enterprises.

Demonstration in Aswan in connection with the launch of one of the units of the Aswan High Dam. 1968

Water from the Aswan Reservoir irrigates fields reclaimed from the desert

Main characteristics of the waterworks

The Aswan Upper Dam is 3600 m long, 980 m wide at the base, 40 m wide at the crest and 111 m high, it consists of 43 million m³ of earth materials, that is, it is a gravity earth dam. The maximum water flow through all culverts of the dam is 16,000 m³/s.

The Toshka Canal connects the reservoir with Lake Toshka. The reservoir, named Lake Nasser, has a length of 550 km and a maximum width of 35 km; Its surface area is 5250 km², and its total volume is 132 km³.

Lake Nasser is the world's largest reservoir, stretching for five hundred kilometers, the depth of which in some places reaches one hundred and eighty meters. Due to its gigantic size, the lake is more like an inland sea, all the more interesting since it is an inland sea of Africa.

After the construction of the Aswan hydroelectric complex, the negative consequences of the floods of 1964 and 1973, as well as the droughts of 1972–1973 and 1983–1984, were prevented. A significant number of fisheries have developed around Lake Nasser.

Ecological problems

In addition to the benefits, however, the damming of the Nile has caused a variety of environmental problems. Large areas of lower Nubia were flooded, displacing more than 90,000 people. Lake Nasser flooded valuable archaeological sites. The fertile silt, which was washed annually during floods into the Nile floodplains, now lingers above the dam. Nowadays, silt is gradually raising the level of Lake Nasser. In addition, changes have occurred in the Mediterranean ecosystem - fish catches on the coast have decreased as nutrients have ceased to flow from the Nile.

There is some erosion of farmland downriver. Shoreline erosion, due to a lack of new sediment from floods, will eventually cause the loss of fisheries in the lakes, which are currently Egypt's largest source of fish. The lowering of the Nile Delta will lead to an influx of sea water into its northern part, where rice plantations are now located. The delta itself, no longer fertilized by Nile silt, lost its former fertility. The production of red bricks, which uses delta clay, has also been affected. In the eastern Mediterranean there is significant erosion of coastlines due to a lack of sand previously brought by the Nile.

The need to use artificial fertilizers supplied by international corporations is also controversial because, unlike river silt, they cause chemical pollution. Inadequate irrigation control has resulted in some farmland being destroyed by flooding and increased salinity. This problem is exacerbated by weakened river flows, causing salt water to intrude further into the delta.

Mediterranean fisheries were also affected by the dam's construction, as the marine ecosystem was heavily dependent on the rich flow of phosphates and silicates from the Nile. Mediterranean catches have dropped by almost half since the dam. Cases of schistosomiasis have become more frequent, as a large amount of algae in Lake Nasser promotes the proliferation of snails that carry this disease.

Due to the Aswan High Dam, the salinity of the Mediterranean Sea has increased; the salt flow from the Mediterranean Sea to the Atlantic Ocean can be traced for thousands of kilometers in the Atlantic.

In the late 1990s, Lake Nasser began to expand westward and flood the Toshka lowland. To prevent this phenomenon, the Toshka Canal was built, allowing part of the Nile waters to be diverted to the western regions of the country.