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السبت، 16 أبريل 2016

The groundwater potential of El-Wadi el-Gedid
In 1958 President Gamal Abdel Nasser announced the El-Wadi el-Gedid,
(‘New Valley’) project as an alternative to the densely populated ‘old’ Nile
valley. According to the plans, millions of people were to be resettled there
thanks to the deep-well drilling for groundwater. Instantly the cultivation of
new land in the oasis depressions of El-Kharga, Ed-Dakhla, El-Farafra and
El-Bahariya was started. Since the early 1960s the amount of groundwater
extracted there has more than doubled. It is 500 million m3
 annually today.
Recent estimates of the total amount of groundwater available in the Nubian
Aquifer System amount to 150,000 km3
 (Heinl and Thorweihe 1993: 119).
This equals the Nile run-off of 1,800 years or a water column of 75 m over
the entire area of 2 million km2
 (Thorweihe and Heinl 1998: 5). If 1.5 m
of this water were to be used for agricultural purposes annually, the water
would be used up within only fifty years. Recent studies show that in the
last 8,000 years the groundwater recharge has been negligible, so that experts
call the extraction from the Nubian Aquifer System ‘mining of an unrenew-
able resource’ (ibid.: 21). Needless to say, the whole calculation is based on a
purely theoretical model. In fact the situation is much more precarious, for if
groundwater is pumped up, the water table around the borehole falls rapidly
in the shape of an extraction cone. When this is the case, greater energy has
to be used to extract the water. It is generally assumed that the profitability
limit for pumping up water for agricultural purposes lies at a depth of 100
m. In Egypt, a depth of 50 m should not be exceeded, since so far neither
the fellaheen nor the investors in agricultural projects pay for the water, and
the resources of the state are limited. For more than forty years now, the
irrigated agriculture of the El-Wadi el-Gedid project has been unprofitable.
Nevertheless, hopes remain high and there are plans for extending it.

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