Sayano-Shushenskaya hydroelectric station. Why the Aswan Dam is interesting to tourists and engineers - technical features and photos

History of construction

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 more safe places or transferred to countries that helped with the work (Temple Debod in Madrid and Temple Dendur in New York).

Main characteristics of the waterworks

Panorama

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.

After the construction of the Aswan hydroelectric complex, 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.

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 fisheries in the lakes, 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 bricks, which uses delta clay, has also been 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. Insufficient 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.

Aswan Dam tends to increase salinity Mediterranean Sea, and thus 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.

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• southeastern Mediterranean restored ecosystem

The Aswan dams provide clear evidence that Egypt's fundamental problem is far more intractable than John Gunter's terse assessment suggested: “Create more land. Or reduce the number of people. Any solution will end the problem, but none of them are simple." Each dam made large areas cultivable, increasing productivity Agriculture and providing electricity to industry. However, all the positive effect came to naught due to rapid population growth, Once again threatening to exceed the level provided by available resources.

This circumstance is forcing Egypt to implement even more ambitious irrigation projects. Well aware of the importance of dams, Egyptians tend to view them as a prime tourist attraction. In contrast, most foreigners see these structures only as a way to reach Abu Simbel, Philae Island and the Kalabsha Temple, which were rebuilt on a higher site after the construction of a high-rise dam. The views from the top of both dams are quite impressive, so make sure to stop here on your trip.

Old Aswan Dam

Directly upriver from the First Rapids stands Aswan Dam built by the British (1898-1902) and subsequently completed twice in order to increase productivity. This is one of largest structures of this kind throughout the world, 50 meters high, 2 kilometers long, 30 meters thick at the base and 11 at the top. Driving along it, you will definitely notice 180 sluice holes, which are opened during floods, and then, as the water level in the river drops, they are gradually closed in order to at least partially preserve the natural cycle.

Now that the high-rise dam has taken over all water storage and irrigation functions, the old one specializes mainly in generating electricity for the nearby Kim plant, which produces chemical fertilizers. South of the dam you can see among the islands. U eastern end The dam is the former Reservoir Colony, now called Khazan. Built in colonial style The villas are nestled here among green gardens. Minibus taxis and pickups run here from Aswan, but at the time of writing this article they did not take foreign tourists.

In 1952, it became clear that the Aswan Dam could no longer meet Egypt's needs and would not guarantee reliable protection from mass starvation. Nasser promised to build a new high dam six kilometers upriver that would give Egypt a future, lead to the development of new industrial sectors and send electricity to every village. When, under pressure from the United States, the World Bank refused to provide a promised loan, Nasser carried out nationalization to obtain funds for the project and turned to the USSR for help.

Construction of the dam (1960-1971) continued after his death, as did the era of Soviet-Egyptian cooperation. When Egypt decided to install more powerful turbine generators in the late eighties, it bought them from America - after which it turned out that it was with the Russians less problems. Today, to implement a new major project in Toshka, which someone called “ Playground for engineers”, Western European contractors are invited.

• Visit to the high dam

The high dam is located 13 kilometers from Aswan. You can move along it at any time from 7.00 to 17.00. All car occupants must pay a £5 toll. They may be asked to show their passports. At the western entrance to the dam stands the Soviet-Egyptian Memorial - a giant tower in the shape of a lotus flower, built as a symbol of cooperation and the benefits brought by the dam. Both are shown on the heroic bas-relief, made in the style of socialist realism. The high observation deck, which must be reached by elevator, can accommodate only four visitors at a time.

Here you can watch how the concrete from which the dam is built crumbles and experience an attack of dizziness. Near the eastern end of the dam there is a pavilion for visitors (daily, 7:00-17:00), which the keeper will unlock after receiving baksheesh. Among the exhibits is a fifteen-meter model of the dam, plans for its construction (in Russian and Arabic) and a selection of photographs telling about the movement.

Unless you ask to be taken to the tower (burg) or model (mekat), the taxi will simply stop in the middle of the dam so you can take a quick tour. From this excellent position, the height of the dam (111 meters) is difficult to assess due to its fencing, but the length (3830 meters) and width at the top (40 meters) with a width of the base (980 meters) are impressive. From the southern end of the dam you can see beyond Lake Nasser. To the north, you can see the giant 2,100-megawatt power plant located on the eastern bank and the canals through which water flows into the Nile. There are always clouds of fog hanging over them, which are cut through by a rainbow from time to time. Further down the river, among a group of islands, lies Philae Island.

Since foreigners are prohibited from using minibus taxis in Aswan, the only way public transport, going to the high dam, there is a train with third class carriages (runs every hour from 6.00 to 16.00; 1 pound), which goes to Saad al-Ali station, located five kilometers from the eastern end of the dam near the pier where the ferry to the Wadi stops -Halfa, and cruise ships traveling on Lake Nasser. Here, tourists who come ashore are allowed to take a minibus to Aswan (stop next to the station; 1.5 pounds).

Lake Nasser and its impact on the environment

The most striking consequence of the construction of the high dam was the creation of Lake Nasser, which stretches for 500 kilometers and reaches the territory of Sudan. Depth in some places over 180 meters, with a surface area of ​​6 thousand square kilometers, the lake is the largest reservoir in the world and more closely resembles an inland sea. During a decade-long drought, when the Nile water level dropped to its lowest level in 350 years, it saved Egypt from the famine that was ravaging Ethiopia and Sudan.

When heavy rains in 1988 forced the Nile to overflow its banks, the high-rise dam saved Khartoum from flooding. Because due to the destruction of the dam most of Egypt's population would be washed away into the Mediterranean Sea, protecting the dam is a top priority. Radar installations and anti-aircraft systems are located on the surrounding hills. It has not been forgotten that Israel threatened to bomb the dam during the 1967 and 1973 wars and Gaddafi in 1984.

Although the social, cultural and environmental impacts of the dam have yet to be assessed, its arrival has brought with it most of the promised benefits. Egypt was able to convert 700,000 feddans (a measure of area slightly less than an acre) of cultivated land from the ancient estuarine irrigation system to year-round irrigation, doubling or even tripling the number of harvests, and making about a million feddans of desert cultivable.

In addition, the appearance of the dam caused a 30% increase industrial production. It generates electricity for Aswan's chemical and cement plants, Helwan Iron and Steel Works and oil refineries. Fishing and serving tourists on Lake Nasser have become profitable industries. And the new one pumping station Toshka and the Sheikh Zayed Canal, as the Toshka project is implemented, should turn new areas of desert into fertile land.

The main victims are the Nubians, whose homeland was flooded by the lake. Other aspects of the dam's impact on the environment are still being studied. The evaporation of the lake leads to fog, clouds and even precipitation over previously arid areas, and groundwater under the Sahara reaches distant Algeria. Because the dam traps the silt that once brought fertility back to Egypt's fields, farmers now rely on fertilizers. It is possible to prevent soil salinization caused by year-round irrigation only by creating an extensive drainage system.

However, this turns local lands into a source of mosquitoes and bilharzia. Ancient monuments are also exposed to salt caused by rising water levels and increased humidity. Some even believe that the dam has made Egypt more susceptible to earthquakes. Finally, without the silt deposits that regularly filled it before, it is intensively destroyed by the Mediterranean Sea along the entire coast.

According to existing calculations, the lake itself will be filled with silt within five hundred years. Some believe that by then Nubia may once again be covered with lush vegetation, as in the prehistoric period. Others fear international conflicts over water resources in the very near future. When Ethiopia recently began exploring the possibility of building a dam on the Abbay River (the source of the Blue Nile), the Egyptian government warned that any reduction in the amount of Nile water flowing into the (according to the treaty it equals 59 billion cubic meters annually) will be seen as a threat national security, and in the future even more water will be needed.

• Cruises and fishing on Lake Nasser

To appreciate the magnitude of Lake Nasser and see the otherwise inaccessible monuments known as Lake Nasser, Amada and Qasr Ibrim, you must take a cruise. Cruise ships began sailing the lake in 1993 at the initiative of Mustafa al-Gindi, a Nubian born in Cairo. His first two ships were the Eugenie (reminiscent of an early 20th century hunting lodge) and the Qasr Ibrim (built in a typical 1930s Art Deco style, both operated by Belle Epoque Travel in Cairo).

There are currently five other ships sailing on the lake: Prince Abbas, Queen Abu Simbek, Nubian Sea and Tania - all five-star, with the exception of the four-star Tania. Each follows the same route, making a four-day journey from the high dam or a three-day sail from Abu Simbel. The cruise includes visits to the three monuments mentioned above, as well as Abu Simbel and the Kalabsha Temple. Most passengers are members of tour groups who reserve seats in advance before arriving in Egypt.

But participation in the cruise can also be arranged through Belle Epoque in, as well as in agencies located on the Aswan waterfront, such as Eastmar Travel (Nubian Sea) or Travco (Tania). Prices range from $120 to $190 per person per night, including meals and monument visits. Nubian Sea won the competition for the best cuisine. Because drinks on ships are so expensive, some travelers choose to smuggle their own supply on board.

Lake Nasser, among other things, is a great place for fishing fans. It is home to Nile perch (the largest specimen caught weighed 176 kilograms, not far from the world record), eighteen species of giant catfish, including the legendary vundu, large tilapia and the piranha-like terapon. Because tilapia (at the bottom of the food chain) spawn in April, other fish are most abundant during the summer months. Best places for fishing are located in the north, to Amada. To the south, most of the fish serve as food for crocodiles.

Several operators in Aswan organize special tours for fishing enthusiasts. Contact African Angler, run by former Kenyan safari organizer Tim Bailey, who offer six (£600-£750) and thirteen (£1,090-£1,315) trips (charged in pounds sterling and include flights from with draft on request), or Lake Nasser Adventure, founded by former Eugenie cruise ship manager Pascal Artieda and local fisherman Negrashi. A third agency, El-Temsah, run by Ala Temsah, organizes fishing, duck-hunting and bird-watching trips for small groups (£600 per person per night).

In contact with

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. The minimum number of turbines was determined largest diameter impeller that can be transported down 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[ | ]

Layout of the High Dam, developed by the company "Alexander Gib"

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 and involved several distinguished engineers, including Sir and Sir, 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.

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 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. 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, (English) in New York, to the interim president of Egypt.

Ecological problems[ | ]

In addition to the benefits, however, the damming of the Nile caused many environmental problems. Vast areas of lower Nubia were flooded, displacing more than 90,000 people. Valuable archaeological sites were found under the waters of the Nasser Reservoir. The fertile silt, which annually washed into the Nile floodplains during floods, now lingers above the dam and gradually reduces the depth of Nasser, although the pressure is maintained.

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, Egypt's largest source of freshwater 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 brick, which uses delta clay, was also affected. In the eastern Mediterranean there is significant erosion of coastlines due to a lack of sand previously brought by the Nile.

Artificial fertilizers supplied by international corporations, unlike river silt, cause chemical pollution. Insufficient irrigation control has led to the destruction of some farmland due to flooding and salinization.

Mediterranean fisheries resources were also affected by the construction of the dam, as the marine ecosystem was heavily dependent on the rich flow of phosphates and silicates from the Nile - Mediterranean catches were reduced by almost half. Cases of schistosomiasis have become more frequent due to the large amount of algae in the reservoir. Nasser promotes the reproduction of snails that carry this disease.

In the late 1990s, the Nasser Reservoir began to expand westward and flood the Toshka Lowlands. 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 Toshka Canal connects the reservoir with Lake Toshka. 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 Aswan Dam is the largest hydraulic system of structures in Egypt, located on the Nile River near the city of Aswan (the first cataract of the Nile). It successfully solved the flood problem and brought control of the river.

Construction of the Aswan Dam

The first dam on the Nile River was built in 1902, thirty years later it was built on, but still it could not cope with the river waters, which is why the need to build a new dam arose. The project was developed in Germany, took part in the installation work Soviet Union. A contract was concluded between Egypt and the USSR for the construction of the Aswan Dam and hydroelectric power station; Moscow provided Cairo with a loan in the amount of 400 million rubles, and also supplied raw materials, equipment and workers.

The process of constructing the dam was complex and time-consuming. The work required such a quantity of sand, clay, stones and concrete that seventeen Cheops pyramids could easily be built from all this. In addition, the surrounding area had to be cleared, for which the houses of more than sixty thousand Egyptians were demolished. Many natural and historical monuments were flooded. The island of Philae completely disappeared, the temples from it were cut into pieces, and then they were collected on another island.

Relocation of architectural monuments

The relocation of the famous rock temples at Abu Simbel caused great difficulty. Both temples were carved out of solid rock, and the facade of one of them was guarded by giant statues of the pharaoh, reaching twenty meters in height. To protect the statues from water, they built a large glass House– visitors were brought down in special vessels. As a result, temples and statues were cut out of the mountain, sawed into blocks and put back together in another place.

The grand opening of the Aswan Dam took place in January 1971 with the participation of Egyptian President Anwar Sadat.

Peculiarities

The dam is an earthen dam with a stone granite fill; the core is formed by clay and cement. The base of the dam is wide - 975 meters, narrowing to forty meters towards the upper edge. On the right bank there are canals and six tunnels - they supply water to the hydroelectric power station. At the beginning there is a semblance of a triumphal arch through which cars can drive. At the top of the dam there is a four-lane road. At the other end of the dam there are monoliths that form a circle and symbolize the sacred lotus flower.

The Aswan Dam in Egypt created a huge artificial reservoir, which was named after the President of Egypt, Nasser. Today it is one of the largest artificial lakes in the world, with an area of ​​5244 square kilometers. The water from it is used to irrigate agricultural lands.

Aswan Dam for tourists

The Aswan Dam as a landmark is included in most tourist routes in Egypt. Many call it the pyramid of the twentieth century. The Aswan Dam tour involves a trip along the Nile on a five-star ship. You can also choose a separate sightseeing tour lasting three hours. Tourists can climb to the top of the dam, along which the road runs, and see the monument to the dam builders. The program includes a visit architectural structure in the form of a lotus flower. Finally, a walk along the Nile on felucca boats.

• On Aswan hydroelectric power station Twelve generators with a total capacity of 2100 MW have been installed.
• During the construction of the dam, 24 archaeological sites were moved to safe places.
• On one of the banks there is a “nilometer” - a device that allows you to measure the water level in the Nile. This is a well with many numbered steps going down to the river.
• The dam project was developed in the Ukrainian city of Zaporozhye. On the territory of the Right Bank quarry of Zaporozhye, a reduced working copy of the Aswan Dam (scale 1:50) was also created. The experimental layout has survived to this day.

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 participated in the construction different countries peace.

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 Nasser nationalized the Suez Canal, intending to use tolls on passing ships to subsidize the Upper Dam project, 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. In the midst cold war in the struggle for third world countries, 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 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 Soviet of the USSR N.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.

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.

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 many environmental problems. Large 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, 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 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 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.

Aswan dam – type from space

Aswan dam – type from space