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(2, 2001) Great
projects on the Nile Basin - a historical perspective by Irina Springuel
Unit
of Environmental Studies and Development, South Valley University, Aswan,
Egypt The
Nile in ancient time The
River Nile in its past history was very vulnerable and unpredictable. The late
Paleolithic was a period of alluviation in the Nile Valley. The river carried
a much higher sediment load than today. The base level of the river was nearly
16m higher than at present time 21, 000 years ago. It was also a period of
hyper aridity; the uplands beyond the valley were devoid of vegetation and
exposed to wind erosion (Wendorf& Schild, 1989). Archeological excavations
of the settlements on the Nile Valley from this period in Wadi Kubbaniya, 15
km south of present Aswan city, were led by Fred Wendorf for more than 10
years. These excavations revealed the ephemeral character of the settlements,
which involved the reuse of key areas to exploit a variety of seasonal
resources (Wendorf& Schild, 1989). The advent of the Holocene wet phase
had its impact on the Nile; it changed it into a perennial and a more
predictable river under which life became more tolerable (Said, 1993). However,
it was not until the middle of Holocene when drought began and drove large
numbers of the Saharan dwellers to the Nile Valley. The river valley had
indeed become a suitable place for agricultural use. The settlers in the
valley found the flood plain of the river an ideal location begin farming, and
to harvest at least one crop a year (Said, 1993). This practice soon led to
the development of the system of basin irrigation and 'fluviatile'
civilizations emerged along a large part of the river valley, of which Egypt
was the 'crown' (Rzoska, 1976). By
the late Predynastic time, the ancient Egyptian hydraulic civilization with
all its distinctive aspects, such as the state, kingship, the royal funerary
cult and true political capitals had become established (Said, 1993). This
civilization was flourishing in the Pharaonic era when most of the spectacular
temples, palaces and royal toms were built in the vicinity of the Nile. Although
the oldest agricultural sites in Egypt which are found on the margins of
western Delta and in the Fayum depression date from 5200-4000 B.C.,
agriculture developed slowly in Egypt. As late as Predynastic times Egypt was
still an amalgamation of hunters and gatherers,
desert herders, farmers and Nilotic fishermen. They supported themselves
through a mixture of herding, fishing and farming even though they lived in
villages and towns (Hoffman, 1979). Even
in the present time the Bedouins, who have settled in villages and towns of
Upper Egypt, still kept their herds in the surrounding desert . It is not
unusual to see flocks of sheep and also goats on the streets of Aswan. Nilometers The
Holocene wet phase terminated around the end of Dynasty V when the rainfall
was at its present-day level. This was the period when the last waves of
desert dwellers moved from the desert to the Nile Valley. These new settlers
increased the population in the valley, resulting more intensive land use,
particularly agriculture. In the ancient past and until the present century,
control of the Nile was the concern of only one country, Egypt, whose
population has always been dependent on the river. Hydrological observations
in ancient times were confined to the most important event of the year; the
arrival and the level of the flood. Four millennia ago, the ancient Egyptians
recorded river levels on Nilometers, some of which have survived until today.
The Nilometers were constructed in the precincts of a temple to record the
height of the water. The Nilometer measurements were closely related to the
fecundity of the land. They determined the area of land that was to be
inundated and the duration of the flood as well as giving the flood warn (Rzoska,
1976; Said, 1993). The
most renowned Nilometers include the 'House of Inundations', presently
situated in Old Cairo, and one at Elephantine Island in Aswan near the First
Cataract; and much later, the most famous Nilometer at Roda was constructed.
It was build at the beginning of the Arab period (715 A.D.) on the southern
tip of Roda island opposite Old Cairo and rebuilt in the years 814-816 A.D.,
and was again renovated to acquire its present form in 861 A.D. The Roda
Nilometer contains a records of the water level, although not continuous, from
the time of its construction onwards, which is the longest catalogue of river
flow in the world. At present there are about 300 stations in Egypt, the Sudan
and Uganda which gauge the river every day (Said, 1993). Ancient
projects The
system of basin irrigation is old. The reclamation schemes on the left bank of
the Nile The
basin system of irrigation was designed to capture the flood water for the
cultivation of a single winter crop. Land use in Dynamic Egypt shows a simple
pattern of winter agriculture. The conservative nature of Ancient Egyptian
civilizations can be partly attributed to the fact that throughout almost the
entire length of the Dynastic period the river was relatively high and
predictable. Of 820 floods recorded on the Roda Nilometer, south of Cairo,
between the seventh and fifteenth centuries, 73% were normal floods that
reached a height which inundated all the basins and subsided at the suitable
time for sowing while 22% were low, and only 5% were destructively high (Said,
1993). Ptolemaic
projects - introduction of lift irrigation The
introduction of more sophisticated mechanized irrigation brought about an
agricultural revolution. The saqia
(water wheel), able to lift substantial quantities of water, was introduced in
early Ptolemaic times, 323-30 B.C. (Chesworth 1994). The use of waterwheels
enabled the Ptolemites to greatly expand the agricultural land of Egypt and
reclaim the Fayum. The drying up of the lake from its previous level of 20
metres above sea level to about two metres below sea level occurred during the
latter part of the reign of Ptolemy I (323-285 B.C.), who conceived the idea
of reclaiming a portion of the submerged area of the Fayum by lowering the
water level of lake. This enormous project added about 325, 000 acres of
fertile arable land to Egypt, thus increasing the wealth of Egypt. Nineteenth
Century Projects The
basin irrigation was the only system known in Egypt for 5, 000 years that
supported agriculture for a sparse population. The introduction of perennial
irrigation was a slow process. In
the early nineteen century Mohamed Ali Pasha began to change the system of
basin irrigation. A large part of the Delta land was converted to perennial
irrigation. The use of the land all-the-year-round meant that water had to be
available in the summer, when the Nile is low, to allow the cultivation of
summer crops. Among these the most important was cotton production, which
increased from 600, 000 to 2, 000, 000 kantars (45 kg) between 1860 and 1864
and reached 6, 440, 000 kantars by 1900 (Chesworth 1994). Barrages Technological
changes which have influenced the Nile's ecosystem include a series of
barrages designed to lift the water level at particular points and dams
designed to store water and/or to produce hydroelectric power. Coupled
with the barrages and dams has been, in certain cases, the drainage of swamps
to unsure more rapid runoff and the creation of intricate system of canals
and drains in the irrigated lands commanded by the barrages (Worthington,
1972). Early in the nineteenth century, Mohamed Ali Pasha started the great
series of barrages whose function was not to store water but to lift the level
of the river in order to regulate a system of canals at all times of the year. Mohamed
Ali built the original Delta barrage just below (north) Cairo to control the
Rosetta and Damietta branches of the Nile. Its architecture was reminiscent of
a medieval castle, but it served well and was not replaced until 1940. Since
then the new Mohamed Ali Barrage has regulated the whole Delta, aided by the
Zifta Barrage on the Damietta branch (Worthington, 1972; Said, 1993). The
next barrage to be constructed was at Assiut in 1902. It was enlarged in 1938
and it provides for perennial irrigation in middle Egypt with one of its
canals running as far as Fayum. It was followed by the Esna Barrage in 1909
which was remodelled in 1947 and recently
replaced. The barrage at Nag-Hammadi was completed in 1930. Their function has
altered since the construction of High Dam at Aswan in the 1960s which enabled
the whole of Egypt to change over to perennial irrigation (Worthington, 1972;
Chesworth 1994). Dams Dams
have a function entirely different from that of barrages. The need for storing
Nile water when the river is at a high stage with both the Blue Nile and
Atbara in flood, so that water would be available at its low stage, was
appreciated well before the end of 19th century. The
Aswan Dam was completed in 1902 . The capacity of its reservoir was more
than doubled by the first raising of its height in 1912 and was multiplied
fivefold in 1934. The Aswan Dam was the first major project since Lake Moeris
to alter the inter-year variation in the Nile discharge, thus storing a part
of the flood for use the following summer. However, it could not save all the
water from years with high flood to be used in years with low floods. The dam
at Jebel Aulia on the White Nile
was completed in 1937. Its function is to hold back part of the White Nile
while the Blue Nile is in flood; but since the valley above Jebel Aulia is
very flat and open a great deal of water is lost by evaporation and seepage (Worthington,
1972). The
Owen Falls Dam
(1954) was the first system of control the White Nile is in Egypt's interest
as well as the countries through which the river runs. It has hydroelectric
power as its primary function but, at the same time, controls the outflow of
Lake Victoria, which it converts into a reservoir of 67, 000 square kilometres.
This project was put forward in 1946 in connection with the first ten-year
Uganda development plan and was designed to meet the requirements of Uganda on
a part with those of Egypt (Worthington, 1972). The
Sennar Dam on the Blue Nile was completed in 1925. Its main function is to
provide water for the Gezira irrigation scheme which still provides the basis
for Sudan's economy (Worthington, 1972). Further
upstream, near the Sudano-Ethiopian border, is the
Roseires Dam and reservoir (50 kilometres long and a maximum depth of 50
metres). This was completed in 1966 and has the primary purpose of greatly
increasing the Blue Nile storage, and also has a hydroelectric installation.
The Khasm el Girba Dam was also
completed in 1966 on the Atbara river. Aswan
High Dam The
High Dam was primarily designed to store water, so that there would be no
excess beyond Egypt's actual needs of 55.5 billion cubic metres, as permitted
under the Nile Waters Agreements (1929 and 1959), and to assure that minimum
flow would be maintained, regardless of whether there was a flood or a drought
upstream (White, 1988). The most obvious and immediate effects of the Aswan
High Dam were felt in the reservoir area where the newly-formed lake inundated
forever the long strip of land which was the home of close to 400, 000 Nubians
(Said, 1993)1 and where an array of temples, tombs and fortresses
stood. The Nubians were evacuated and resettled in the new lands reclaimed in
the south of Egypt and north of the Sudan. The
imminent flooding of many temples, tombs and fortresses along the Nubian
stretch of the river gave rise to an great international campaign to save some
of these archeological monuments and treasures. The process of damaging of
these monuments started with the second heightening of the Aswan Dam in 1912
when the reservoir flooded most of the sites for a certain period of year. The
building of Aswan High Dam threatened the total loss of all monuments below
the waters of the permanent lake. On 8 March 1960, the Director-General of
UNESCO inaugurated the 'International Campaign to save the Monuments of Nubia'
by saying: "work has begun on the great Aswan Dam. Within five years, the
Middle Valley of the Nile will be turned into a vast lake. Wondrous structures,
ranking among the most magnificent on earth, are in danger of disappearing
beneath the waters.... It is, therefore, with every confidence that I invite
governments, institutions, public or private foundations, and men of good-will
everywhere, to contribute to the success of a task without parallel in history"
(Kassas, 1972). All the free-standing temples and other ancient buildings
capable of being moved were transferred to new sites. The Kalabsha, Betel-Wall,
Qertassi, El-Moharraqqa, El-Sebu and El-Dakka temples were all moved to higher
ground. One
of the major concerns was that the proposed reservoir would flood the Isis
Temple on Philae (actually a large complex of monuments built from late
Pharaonic to Roman times on the island at the head of the First Cataract about
10 kilometres south of Aswan). The Philae temple was the last link with
Pharaonic civilization in Egypt before being sacked by '
White (1988) give figure of 110, 000 Nubians evacuated from them mother land. Christians
at the end of sixth century A.D., and was thus an archaeological site of major
importance (Whittington & Gueriso, 1983). The building of a cofferdam
around the island of Philae and transfer of monuments to the nearby island of
Agilkia were completed by 1979. The salvage of the rock-cut temples of
Abu-Simbel, which started in 1969, was a monumental feat in both its
engineering and financing. The $40 million programme was financed in part by
an international fund organized by UNESCO, with the Egyptian government paying
about half of the cost. The
Equatorial Nile Project The
development of large scale irrigated agriculture in Egypt and Sudan required
the continued extension of annual storage facilities in the Nile basin. The
Equatorial Nile Project also known as the Century Storage Plan involved not
only releasing water according to seasonal irrigation requirements in Egypt,
but annual storage to obtain a quaranteed and predictable flow every year. The
Century Storage Scheme proposed by Hurst ( Hurst et
al 1966) entailed the following new projects in the upstream Nile basin: 1.
A new main Nile reservoir in the region between the Atbara and Wadi Halfa, to
be used for flood protection and also for summer storage. The Construction of
Aswan High Dam fulfilled the requirements of year to year storage required for
Egypt. 2.
A reservoir for year to year storage in Lake Albert, combined with a regulator
on Lake Victoria. The government of Uganda proposed a reversal project with
the main storage in Lake Victoria and Lake Albert as a regulating reservoir. 3.
A diversion canal in the Sudd Region 4.
A reservoir for year to year storage in Lake Tana. The
linchpin of the plan was the use of the equatorial lakes as reservoirs but not
fully implemented yet. These lakes would make perfect reservoirs because
losses by evaporation from their surfaces would be minimal being roughly
balanced by rainfall. References: E.
Barton Worthington 1972, The Nile catchment-Technological change and aquatic
biology in M.Taghi Farvar & John P.Milton ed. The
Careless Technology. The natural History Press/Garden City, New York. Chesworth,
P.M. 1994. The history of water use in the Sudan and Egypt in Eds Howell P.P. and
Allan, A. The Nile: Sharing a scarce
resources. Cambridge University Press. Kassas M., 1972, Ecological
Consequences of water Development Projects. In Polunin, N. Ed.
The Environmental Future. Published
by The Macmillan Press Ltd. Hoffman, M.A.1979, Egypt before the Pharaohs.
Alfred A. Knopf, New York. Hurst, H.E.; Black R.P. & Simaika Y.M. 1966., THE
NILE BASIN. Volume X The Major Nile Projects.
Cairo, General Organization for Government Printing Offices Rzoska, J. 1976,
Nile Water-Hydrology Past and Present in J. Rzoska ed. The
Nile, Biology of an
Ancient River.
The Hague Said,
R. 1993 THE RIVER NILE Geology,
Hydrology and Utilization. Pergamon Press Wendorf, F and Schild, R. 1989. The
Prehistory of Wadi Kubbaniya, Vol.2 Stratigraphy. Paleoeconomy,
and Environment. Southern Methodist University Press. Dallas Whittington, D.
and Guariso, G. 1983 Water Management
Models in Practice: A Case Study of
the Aswan High Lake. Elsevier Scientific Publication Company. White, G.F. 1988
The Environmental Effects of the High Dam at Aswan. Environment,
vol.30 No7:
5-40.
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