The High Aswan Dam was built across the Nile in Aswan city, Egypt and It is considered the world's largest embankment dam .The High Dam has had a significant effect on the economy and culture of Egypt . Before the dam was built the Nile use to flood every year. Although this fertilised the surrounding land and helped crop growth it did occasionally cause problems.
Sometimes the flood was too high and it destroyed all the crops. Other times the flood was too low and so could not effectively fertilise the soils. After several successive years of low water a famine occurred and many people died. Something was needed to regulate the flow of water and so, in 1954, the High Aswan Dam project was started. By 1968 the reservoir behind the dam, Lake Nasser, was full.
Benefits and Disadvantages of The High Dam of Aswan
Benefits
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Disadvantages
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- A secure water supply has meant an extension of irrigated
land along the edge of the desert and increased crop yields.
- Hydro-electric power station supplies electricity to
surrounding area.
- Created jobs and has been the catalyst for economic expansion
along the banks of the Nile.
- Protects the length of the river against flooding.
- Reservoir created is a large reliable water source, enough to
supply the Nile for 3 years should a
drought occur.
- Reservoir has also improved tourism and provided facilities
for fishing.
- Navigation of the River Nile made easier as the depth of
water is controlled.
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- Decline in water quality. There are high levels of pollution
in the Nile because the irrigated water
is returned to the river
- Loss of nutrients in soil because annual floods have been
stopped – increased use of chemical fertilisers – increase in pollution
and health problems
- Dam traps silt which before help give nutrients to the soils.
Also reduced silt has caused the shoreline of the Nile Delta to retreat
and decreased offshore fish stocks.
- Increase in erosion on the river banks which has caused the
loss of agricultural land.
- 120 000 people forced to resettle from the dam and reservoir
area.
- Salinization has occurred on newly reclaimed land (previously
the floods washed the salts from the soil.)
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