Case Study: The Aswan High Dam, Egypt – Power and Energy in Africa (Senior 3 Geography) | Ganzaa

Power and Energy in Africa

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Senior 3 · Geography

Power and Energy in Africa

4 lessons

Lesson 3 of 4

Case Study: The Aswan High Dam, Egypt

35 min

Let's begin

For thousands of years, Egypt lived by the rhythm of the Nile flood. Each year the river rose, spread over the valley and left a layer of fertile silt; in a bad year it rose too little and people went hungry, and in a very high year it swept villages away. On 21 July 1970 the Aswan High Dam was completed, and the flood stopped. Behind the dam, a lake 500 km long now stores the river's water. Was taming the Nile a triumph, or did Egypt pay too high a price?

Location and facts

Feature	Fact
River and place	The Nile at Aswan, southern Egypt, just above the First Cataract
Built	1960 to 1970, with loans, machines and engineers from the Soviet Union
Size of dam	111 m high and 3,830 m long; an embankment dam of rock and clay
Reservoir	Lake Nasser: about 500 km long, up to 35 km wide, 5,250 km² in area; its southern end, in Sudan, is called Lake Nubia
Power	12 turbines with an installed capacity of 2,100 MW
Main purposes	Flood control, water storage for irrigation, and hydroelectricity

Definition

Multipurpose dam: a dam built for several uses at once, such as power, irrigation, flood control, water supply and fishing. Perennial irrigation: irrigation that supplies water all year round, so that two or three crops can be grown each year. Basin irrigation: the older Egyptian method of letting the annual flood fill walled fields, giving one crop a year. Cataract: a stretch of rapids where a river crosses hard rock.

Factors that favoured the dam

Hard rock: at Aswan the Nile crosses granite and other hard crystalline rocks (the First Cataract), which give firm foundations.
A narrow valley that shortened the dam.
A large, permanent river: the Nile is fed by heavy rain on the Ethiopian Highlands and by the lakes of East Africa, including Lake Victoria.
A thinly populated desert valley upstream in Nubia, where a reservoir could be made (though over 100,000 people still had to move).
A large market: Egypt's growing population, Cairo and new industries needed water and power.
Capital and technology from the Soviet Union, and the strong will of President Nasser's government.
High evaporation and a desert climate meant that Egypt's farms depended totally on stored Nile water.

Benefits

Benefit	Detail
Flood control	No more destructive floods; water stored in wet years protected Egypt during droughts
Irrigation	Perennial irrigation allowed two or three crops a year and new land to be reclaimed from the desert
Hydroelectricity	2,100 MW, more than twice Egypt's total capacity in 1960; in 1970 it gave about half of Egypt's electricity and brought power to most villages for the first time
Industry	Power for fertiliser and metal industries and for Egypt's towns
Navigation, fishing and tourism	A steadier river for boats; a new fishery on Lake Nasser; visitors to the dam and to Abu Simbel

Problems

People moved: Lake Nasser flooded much of Nubia, and 100,000 to 120,000 people were resettled in Egypt and Sudan, losing their homeland.
Lost heritage: many archaeological sites were drowned; 22 monuments, including Abu Simbel, were moved in a UNESCO rescue.
Loss of silt: the silt that once fertilised the fields now settles in Lake Nasser, so farmers must buy artificial fertiliser.
Coastal erosion: without new silt, the Mediterranean coast of the Nile Delta is being worn away.
Waterlogging and salinity: perennial irrigation raised the water table, drawing salt into the soil, which needed costly drainage.
Evaporation: 10 to 16 km³ of water evaporates from Lake Nasser each year.
Fewer sea fish: Egypt's Mediterranean catch fell from 35,000 to 40,000 tonnes a year to 20,000 tonnes or less, because the plankton fed by Nile silt declined.
The reservoir is silting up slowly, though estimates still give the dam at least 200 years of service.

Worked example

Worked example 1: water saved and water lost. About 10 km³ of water evaporates from Lake Nasser each year, yet the water available for irrigation rose by 22 km³ a year. How much water was stored in total each year, and what share was lost to evaporation?

Total = 22 + 10 = 32 km³.
Share lost = 10 ÷ 32 × 100 = 31.3%.
Conclusion: nearly a third of the water saved by the dam is lost to the desert air, but Egypt still gains a large amount.

Worked example

Worked example 2: the sardine catch. Egypt's Mediterranean catch fell from about 35,000 tonnes a year to about 20,000 tonnes. Calculate the percentage fall.

Fall = 35,000 − 20,000 = 15,000 t.
Percentage fall = 15,000 ÷ 35,000 × 100 = 42.9%.
Conclusion: trapping the silt behind the dam affected life far away, at the mouth of the river.

Warning

Check old claims against the evidence. Many textbooks say the dam spread bilharzia (schistosomiasis). Studies show the opposite: perennial irrigation was already common before the dam, bilharzia declined in Upper Egypt within 15 years of the dam's closure, and treatment campaigns in the 1990s cut it further in the Delta. Do not use bilharzia as an effect of the dam.

Tip

Structure a case-study answer in four parts: location (river, country, map), factors for the site, benefits and problems, then a short judgement. Add at least two figures, such as 2,100 MW and 100,000 people resettled.

Middle East Info: how the Aswan High Dam transformed Egypt and why it stirred controversy. Sort the effects you hear into benefits and problems.

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Practice

Define multipurpose dam and perennial irrigation.
Locate the Aswan High Dam and name the lake behind it.
Give four physical and human factors that favoured building the dam at Aswan.
Describe three benefits of the dam to Egypt.
Explain why farmers below the dam now use more artificial fertiliser.
The dam has 12 turbines and an installed capacity of 2,100 MW. What is the capacity of each turbine?
Explain how the dam has affected the coast of the Nile Delta.
"The Aswan High Dam has done Egypt more good than harm." Evaluate this statement.

Show answersHide answers

Multipurpose dam: a dam built for several uses, such as power, irrigation and flood control. Perennial irrigation: irrigation that supplies water all year, allowing two or three crops a year.
On the River Nile at Aswan, in southern Egypt; the reservoir is Lake Nasser (Lake Nubia in Sudan).
Any four: hard granite rock; a narrow valley; a large permanent river; a thinly populated desert valley upstream; a large market for water and power; Soviet capital and technology; government determination.
Any three: flood control and drought protection; perennial irrigation and new farmland; 2,100 MW of electricity and power to villages; industry; fishing on Lake Nasser; navigation; tourism.
The silt that once spread over the fields each flood is now trapped in Lake Nasser, so soil fertility must be kept up with artificial fertiliser.
2,100 ÷ 12 = 175 MW.
The Nile no longer brings new silt to the delta, so waves wear the coast away faster than it is rebuilt, and the coastline retreats.
Good: flood and drought protection, two or three crops a year, electricity and industry. Harm: over 100,000 people moved, lost heritage, loss of silt, coastal erosion, salinity, evaporation, fewer sea fish. A judgement: more good than harm for Egypt's food and power, but the costs fell on the Nubians, the delta and the environment.

Sources and credits

Aswan Dam, Lake Nasser and Abu Simbel: Wikipedia contributors, Wikipedia, CC BY-SA 4.0, adapted by Ganzaa.
Figure 4 drawn by Ganzaa on country outlines from Natural Earth (public domain).
Photo: Power plant, Aswan High Dam, Aswan, Egypt, Vyacheslav Argenberg, Wikimedia Commons, CC BY 4.0.
Photo: Abusimbel, Per-Olow Anderson, Wikimedia Commons, public domain.
Video: How THIS Dam Transformed Egypt and Stirred Controversy, Middle East Info, embedded from YouTube.
Figure 4, tables, worked examples and exercises: written by Ganzaa.

This lesson adapts CC BY-SA material and is shared under CC BY-SA 4.0.

1Location and facts

2Factors that favoured the dam

3Benefits

4Problems

Location and facts

Factors that favoured the dam

Benefits

Problems