Detecting and Controlling the Waterlogging in Dakhla Basin
243
issue, we seek to understand the current problems of waterlogging in Dakhla Basin
in relation to the potential of Egyptian agriculture in providing a growing population with agricultural products. To sum up; this chapter aims at gaining knowledge
and understanding of the waterlogged, which affects the possibilities for agricultural
expansion into the New Valley.
2 Study Area
2.1 Kharga-Dakhla-Farafra Depressions
The depressions of Kharga and Dakhla are one Depression as they are surrounded by
steep escarpments from the east and north without imperceptible breaks and shifts.
This mega-depression stretches for about 350 km east-west but has a distance of
200 km north-south along its eastern border in Kharga and about 50 km in Dakhla.
Surrounding plateaus rise 300 m a.s.l east of Kharga, 500 m on Abu Tartur, and
300–350 m asl on the northern plateau of Dakhla. From a historical point of view, in
classical times, the two oases of Kharga and Dakhla were called “Oasis,” referring
together to Kharga and Dakhla as “Oasis Magna” (great oasis), while Bahareya was
called “Oasis Parva” (small oasis). Two depressions forming “Oasis Magna” were
connected together during the Middle Ages by the caravan route called “El Ghabari,”
which is now overridden by the modern asphalt road.
Two major rivers ruled eastern Libya, the Sahabi in the west and the Kufra in
the east, although the latter seized the former and controlled the paleohyderological
network in eastern Libya in the Early Pliocene. The third is a significant conduit
of freshwater; the Gilf River, which linked the Uwainat—Gilf high in southwestern
Egypt to the north Mediterranean Sea. It may be clear that most of the depressions in
the Western Desert, specifically Kharga-Dakhla–Farafa (Fig. 1), are hydrologically
connected to this paleo Gilf River. Figure 1 shows the location of Dakhla and Kharga
Oases and surrounding landmarks as well as the approximate northeastern boundary
(saline freshwater interface) of the Nubian Aquifer (Heinl and Brinkmann 1989;
Thorweihe 1990).
The Western Desert extends westward from the Nile Valley to the Libyan border
with an area of some 681 000 km
2 (excluding Faiyum), more than two-thirds of that
of Egypt as a whole. For the most part, its terrain consists of a flat rocky plateau and
high-lying sandy and stony plains with few distant drainage lines. True mountains can
only be seen in the extreme southwest portion where Gebel El-Uweinat’s highest peak
is 1907 m. In the northern and central parts of the Western Desert, large depressions
and oases to break the surface of the plateau at intervals.
Egypt’s topography as showed in Fig. 2 shows that, after obtaining irrigation
water, agricultural expansion could be directed mainly towards the Western Desert,
which has several depressions along the northern third of this desert, such as the
243
issue, we seek to understand the current problems of waterlogging in Dakhla Basin
in relation to the potential of Egyptian agriculture in providing a growing population with agricultural products. To sum up; this chapter aims at gaining knowledge
and understanding of the waterlogged, which affects the possibilities for agricultural
expansion into the New Valley.
2 Study Area
2.1 Kharga-Dakhla-Farafra Depressions
The depressions of Kharga and Dakhla are one Depression as they are surrounded by
steep escarpments from the east and north without imperceptible breaks and shifts.
This mega-depression stretches for about 350 km east-west but has a distance of
200 km north-south along its eastern border in Kharga and about 50 km in Dakhla.
Surrounding plateaus rise 300 m a.s.l east of Kharga, 500 m on Abu Tartur, and
300–350 m asl on the northern plateau of Dakhla. From a historical point of view, in
classical times, the two oases of Kharga and Dakhla were called “Oasis,” referring
together to Kharga and Dakhla as “Oasis Magna” (great oasis), while Bahareya was
called “Oasis Parva” (small oasis). Two depressions forming “Oasis Magna” were
connected together during the Middle Ages by the caravan route called “El Ghabari,”
which is now overridden by the modern asphalt road.
Two major rivers ruled eastern Libya, the Sahabi in the west and the Kufra in
the east, although the latter seized the former and controlled the paleohyderological
network in eastern Libya in the Early Pliocene. The third is a significant conduit
of freshwater; the Gilf River, which linked the Uwainat—Gilf high in southwestern
Egypt to the north Mediterranean Sea. It may be clear that most of the depressions in
the Western Desert, specifically Kharga-Dakhla–Farafa (Fig. 1), are hydrologically
connected to this paleo Gilf River. Figure 1 shows the location of Dakhla and Kharga
Oases and surrounding landmarks as well as the approximate northeastern boundary
(saline freshwater interface) of the Nubian Aquifer (Heinl and Brinkmann 1989;
Thorweihe 1990).
The Western Desert extends westward from the Nile Valley to the Libyan border
with an area of some 681 000 km
2 (excluding Faiyum), more than two-thirds of that
of Egypt as a whole. For the most part, its terrain consists of a flat rocky plateau and
high-lying sandy and stony plains with few distant drainage lines. True mountains can
only be seen in the extreme southwest portion where Gebel El-Uweinat’s highest peak
is 1907 m. In the northern and central parts of the Western Desert, large depressions
and oases to break the surface of the plateau at intervals.
Egypt’s topography as showed in Fig. 2 shows that, after obtaining irrigation
water, agricultural expansion could be directed mainly towards the Western Desert,
which has several depressions along the northern third of this desert, such as the