Cochise College Student Papers in Geology
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Aswan Dam
by Josh Brock
Physical Geology
Fall 2008
Damming the Nile: The Aswan High Dam
Throughout
history, civilizations have been founded, and sustained by the life-giving
properties of major rivers, such as the Nile. Inevitably, as a species, we
always strive to safeguard and take control of such resources, wrangling them in
so that they may become more advantageous to our needs. There can be no more
perfect example of the benefits, and downfalls, of this control than the Aswan
High Dam, in Egypt.
(NASA
Satellite Image of Aswan High Dam) (1)
The Aswan High Dam
was a project that began its infancy in 1954 after the Egyptian Revolution,
where the political climate was finally ripe for the construction of a new,
modern, super damn. Not surprisingly, the Aswan High Dam was not the first
attempt to tame the mighty Nile, but was made to replace the aging and
maintenance dependant Aswan Low Dam which was constructed by the British in 1902.
The Low Dam, which had to be raised on two separate occasions to
keep from overflowing, was no longer able to keep up its fight against the
river. The British had entertained the notion of raising it a third time, but
the idea was met with stiff opposition.
With the
opportunity granted by the Revolution in 1954, however, the
newly formed government of Egypt actively began planning and seeking funding for
the project.
At first, the United States was set to fund the project, but the
deal was later scrapped due to a shifting political climate. The deal then, not
surprisingly, came to the Russians, who gladly financed the project in 1958.
Construction of the 3, 830m long and 980m wide Dam began in 1960, and reached full capacity by July 1970.
(Aswan Dam Project Design) (2)
The
benefits of the construction of the Aswan Dam can be seen as the global
justification for constructing a Dam. The first and foremost benefit of the
structure is to control the devastating floods that could tear through the Nile
River Valley. Indeed, given the fact that approximately 95% of Egypts
population lives within 12 miles of the Dam(3), this was a very central issue to
consider.
Along with controlling flood waters, the Dam also allowed irrigation
water to be dispersed to the large agricultural region. Farms that were formerly
hampered by either flooding or drought could now increase productivity
dramatically with due to the protection and hydration afforded by the Dam.
Another benefit of constructing the Dam was the production of cheap
electricity. With twelve electric generators rated at 175 megawatts, the Dam
provides 2.1 gigawatts of electricity. This electricity provides much of the
power supply for Egypt.
Aside from electricity, flood control, and farming benefits, the
reservoir created by the Aswan Dam, Lake Nasser, provides a growing fishing
industry. While the industry boasts of growing yield, it is hampered by the lack
of large markets in the area.
(Aswan High Dam) (4)
While the
benefits of Aswan Dam are clearly dramatic, construction of the concrete
behemoth has given rise to numerous environmental issues that were not taken
into account during construction.
The first, and relatively easiest to anticipate, issue was the
displacement of thousands of locals from the project area. Lake Nasser, when
created, occupied an area previously inhabited by over 90,000 Nubians. Along
with displacing these people and in effect destroying their lifestyle, the
flooding caused many archeological sites to be erased and buried under a literal
wall of water.
Next, is the negative effect of the gradual salinization of the Nile
farmland. In the past, the soil in the fertile region was annually replenished
as the river flooded each season. This flooding would wash away the salt
produced by excessive farming, and redeposit a fresh layer of rich soil and
minerals over the area. Now that the Dam has stopped this annual happening, the
soil is beginning to lose its fertility, and is nowhere near as rich today as it
was before the construction of the Dam.
Another agricultural related effect is the chemical pollution of
artificial fertilizers. Once clean of chemical pollutants due to the natural
fertilization process, the waters are now showing signs of contamination as
farmers are forced to rely on man-made materials to increase the productivity of
their fields.
Curiously enough, the Dam has also had a very dramatic effect on the
population of fish near the eastern basin of the Mediterranean. This region,
which is traditionally un-fertile in minerals, used to depend on a flow of
silicates and phosphate from the Nile to provide sustenance for the underwater
life. Now that the flow has been blocked, the fishing industry has taken a hit
and is not expected to recover.
These reasons, combined with a continual build up of silt in the
Nasser Lake Reservoir (an inevitable phenomenon which will eventually decrease
productivity and render the Dam obsolete) are fuel for many debates about the
usefulness of the Dam for the Egyptian Ecosystem and Economy.
(Temple of Abu Simel which was displaced by Dam construction) (5)
In conclusion, Aswan High Dam is a structure which has proven both to be an economical and industrial boon, and an environmental issue. This Dam is representative, in many ways, of the pros and cons of constructing a similar structure all over the world. The debate about the effectiveness of the Aswan High Dam is ongoing, and proves that the potential effects of construction such a project, both good and bad, should be carefully considered and studied in depth.
Sources:
http://earth.jsc.nasa.gov/sseop/EFS/lores.pl?PHOTO=STS102-303-17 (photo) (1)
http://www.proutworld.org/features/nile-filer/image002.jpg (photo) (2)
http://www.pbs.org/wgbh/buildingbig/wonder/structure/aswan_high.html (3)
http://www.mbarron.net/Nile/OWENFALL.JPG (4)
http://www.mbarron.net/Nile/new-sbl.jpg (5)
http://carbon.cudenver.edu/stc-link/aswan1/
http://en.wikipedia.org/wiki/Aswan_Dam
