Saturday, February 27, 2010

Nubian Aquifer link to Sinai

The Nubian Aquifer System

Desert IrrigationWater in Abu Minqar is supplied by 15 deep wells that reach down to depths ranging between 600 and 1,000 meters. Some of these wells are artesian, and others are operated by motorized pump. As the rainfall in Egypt’s Western Desert is virtually zero, the oasis depends exclusively on the water supply from these deep wells, which tap the Nubian Sandstone Aquifer System.

The Nubian Aquifer spans across Sudan, Chad, Libya, and Egypt and reaches Sinai and southern Israel in the North[1]. The aquifer system has a “subsurface extent of over 630,000 km²”[2]. The thickness of the sandstones that contain the artesian flow system ranges from 400 km depth near Kharga Oasis to a depth of over 2 km at Siwa Oasis. The aquifer system is stratified and consists of several different horizons – at Dakhla and Kharga Oases, for example, are two layers: an “upper aquifer, reported at the depth of about 400m”; and a “lower aquifer, reported at a depth of about 650m from the surface”[3].
The Nubian Aquifer System is a source of fossil water, as it was accumulated over thousands of years and experiences “negligible recharge in the present arid conditions”[4]. This means that the water is a non-renewable resource. It is not clear how long ground water will be available for extraction from the aquifer, especially as extraction rates are intensifying in most North-African countries that tap the aquifer system. Currently, about 0.6 billion m3 of water are pumped from deep aquifers in Egypt alone. Within Abu Minqar, the pressure on the aquifer is also increasing as new wells in and around the community are dug, partly by private companies and investors, with future plans for numerous additional wells. How such increased pressure on the finite water resource will impact the sustainability of agricultural production and livelihoods as well as the social cohesion within new settler communities remains a topic for future research.

No comments:

Post a Comment