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 The Nile River is the longest river in the
world, stretching for 4,187 miles. The Nile flows from south to
north and is formed by three major tributaries: the White Nile,
the Blue Nile and the Atbara.
The Blue Nile has its source in the highlands of the African
country of Ethiopia, by Lake Tana. The runoff from spring rain
and melting snow caused the annual summer flood of the Nile that
the Egyptians depended on for water to irrigate their crops, and
deposit fertile top soil.
Just north of Khartoum the combined White and Blue Nile meet
their final major tributary, the Atbara which also has its
source in the Ethiopian highlands.
The Nile then plunges into a canyon. Before the construction of
the Aswan High Dam; the Nile rolled through a series of six
rapids, called cataracts, between northern Sudan and southern
Egypt. Since construction of the dam, the river has gradually
changed its course.
North of Cairo, the Nile splits into two branches (or
distributaries), the Rosetta Branch to the west and the Damietta
to the east.
Lake Nasser is a man-made lake created by the construction of
the Aswan High Dam, opened in 1971. The dam was built to
regulate the flow of the Nile River, and thus benefit the
region's inhabitants. However, technology often also disrupts a
local ecosystem, the life and nature it affects.
The canyon that was once behind where the dam is now, was
flooded after the dam was built. Before the region was flooded
for the dam, some Ancient sites were carefully moved. Others
were permanently covered and destroyed by the water. Lake Nasser
stretches over a distance of 312 miles. Gone are the days when
Egyptians worry that the Nile will flood too high, destroying
their crops; or fall too low, not providing proper irrigation.
To enjoy the benefits of a steady river flow, thousands of
peoples homes were submerged when the dam went into operation
and Lake Nasser was formed.
The Aswan High Dam has caused other changes. The water surface
of the lake has reduced the average temperature in the region.
The dam has also harnessed the water for the production of
electricity and navigation has been improved.
Farmers are forced to use chemical fertilizers because the rich
top soil is now deposited in Lake Nasser instead of along the
banks of the Nile. Furthermore, the Nile is no longer flowing
strongly enough to keep salt water from the Mediterranean Sea
from forcing its way up the Nile. The salt water disrupts the
animal habitat and sterilizes the soil in the northern delta
region where the banks of the Nile are becoming badly eroded.
In one generation, thousands of years of life along the Nile
River have been permanently altered.
Just north of the border between Egypt and Sudan lies the Aswan
High Dam, a huge rockfill dam which captures the world's longest
river, the Nile, in one of the world's third largest reservoirs,
Lake Nasser. The dam, known as Saad el Aali in Arabic, was
completed in 1970 after 18 years of work.Egypt has always
depended on the water of the Nile River. The two main
tributaries of the Nile River are the White Nile and the Blue
Nile. Lake Victoria is the source of the White Nile and the Blue
Nile begins in the Ethiopian Highlands. The two tributaries
converge in Khartoum, the capital of Sudan where they form the
Nile River. The Nile River has a total length of 4,160 miles
(6,695 kilometers) from source to sea
Before the building of a dam at Aswan, Egypt experienced annual
floods from the Nile River which deposited 4 million tons of
nutrient-rich sediment which enabled agricultural production.
This process began millions of years before Egyptian
civilization began in the Nile valley and continued until the
first dam at Aswan was built in 1889. This dam was insufficient
to hold back the water of the Nile and was subsequently raised
in 1912 and 1933. In 1946, the true danger was revealed when the
water in the reservoir peaked near the top of the dam
In 1952, the interim Revolutionary Council government of Egypt
decided to build a High Dam at Aswan, about four miles upstream
of the old dam. In 1954, Egypt requested loans from the World
Bank to help pay for the cost of the dam (which eventually added
up to US$1 billion). Initially, the United States agreed to loan
Egypt money but then withdrew their offer for unknown reasons.
Some speculate that it may have been due to Egyptian and Israeli
conflict. The United Kingdom, France, and Israel had invaded
Egypt in 1956, soon after Egypt nationalized the Suez Canal to
help pay for the dam
The Soviet Union offered to help and Egypt accepted. The Soviet
Union's support was not unconditional, however. Along with the
money, they also sent military advisers and other workers to
help enhance Egyptian-Soviet ties and relations
In order to build the dam both people and artifacts had to be
moved. Over 90,000 Nubians had to be relocated. Those who had
been living in Egypt were moved about 28 miles (45 km) away but
the Sudanese Nubians were relocated 370 miles (600 km) from
their homes. The government was also forced to develop one of
the largest Abu Simel temple and dig for artifacts before the
future lake would drown the land of the Nubians.
After years of construction (the material in the dam is the
equivalent to 17 of the great pyramid at Giza), the resulting
reservoir was named for the former president of Egypt, Gamal
Abdel Nasser, who died in 1970. The lake holds 137 million
acre-feet of water (169 billion cubic meters). About 17 percent
of the lake is in Sudan and the two countries have an agreement
for distribution of the water.
The dam benefits Egypt by controlling the annual floods on the
Nile River and prevents the damage which used to occur along the
floodplain. The Aswan High Dam provides about a half of Egypt's
power supply and has improved navigation along the river by
keeping the water flow consistent.
There are several problems associated with the dam as well.
Seepage and evaporation accounts for a loss of about 12-14% of
the annual input into the reservoir. The sediments of the Nile
River, as with all river and dam systems, has been filling the
reservoir and thus decreasing its storage capacity. This has
also resulted in problems downstream.
Farmers have been forced to use about a million tons of
artificial fertilizer as a substitute for the nutrients which no
longer fill the flood plain. Further downstream, the Nile delta
is having problems due to the lack of sediment as well since
there is no additional agglomeration of sediment to keep erosion
of the delta at bay so it slowly shrinks. Even the shrimp catch
in the Mediterranean Sea has decreased due to the change in
water flow.
Poor drainage of the newly irrigated lands has led to saturation
and increased salinity. Over one half of Egypt's farmland in now
rated medium to poor soils
The parasitic disease schistosomiasis has been associated with
the stagnant water of the fields and the reservoir. Some studies
indicate that the number of individuals affected has increased
since the opening of the Aswan High Dam.
The Nile River and now the Aswan High Dam are Egypt's lifeline.
About 95% of Egypt's population lives within twelve miles from
the river. Were it not for the river and its sediment, the grand
civilization of ancient Egypt probably would have never existed.
The construction of the AHD, which can be considered an
irrigation revolution for full utilisation of Nile water,
entailed the introduction of regulated agriculture and
controlled irrigation. Accordingly, farmers, who constitute the
main beneficiaries of the AHD project, enjoyed numerous
advantages. These include:
· guaranteed availability of irrigation water at any
predetermined period for agricultural production,
· improved management of water supply throughout the Egyptian
water system, resulting in a transfer of about one million acres
from seasonal to perennial irrigation,
· agricultural expansion in millions of acres of new land owing
to increased water availability,
· protection from high floods as well as from low floods, and
· generation of hydroelectric power to supply villages with
electricity
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