Regional Strategy for the utilization of Nubian Sandstone Aquifer System

Omar Elbadawy

CEDARE

In the North Eastern part of Africa, lies the Nubian Sandstone Aquifer System (NSAS),

which is shared between Egypt, Libya, Sudan and Chad. The aquifer system underlies an

area of about 2.2 million km2, 828,000 km2 of which is in Egypt, 760,400 km2 is in East

Libya, 235,000 km2 is in North Chad and 376,000 km2 is in North Sudan. The area

occupied by the aquifer extends between Latitudes 14 and 33 and longitudes 19 and 34.

Recent isotope hydrogeological studies indicate that the Nubian Sandstone Aquifer

System is non-renewable. A study funded by the International Fund for Agriculture

Development (IFAD) and executed by the Centre for Environment and Development for

the Arab Region and Europe (CEDARE) has concluded that the replinishment of the NSAS

may have stopped some 8000 years ago, which indicated the end of the rainy era in that

region. Groundwater extractions from the NSAS started in 1960 and resulted in the

decline in water levels in areas of development.

Water scarcity is an overwhelmingly important constraint to development in the region.

The non-renewability of the Nubian Sandstone Aquifer, and the lack of information on

great portions of the aquifer poses more complexity on the management of the aquifer.

It is considerably important to employ rational principles in the utilization of the aquifer

and to predict the aquifer response to different scenrios of groundwater utilization.

A finite element mathematical model was developed to simulate development

scenarios, to analyze the aquifer’s behavior, and to predict its response to future

groundwater abstractions within a regional perspective.

Monitoring of the aquifers (extraction, water level and water quality), especially in and

around the development areas, should continue, so as to regularly update and possibly

improve the model. In this respect the proposed sites for regional monitoring network

should be completed as soon as possible, particularly for Siwa, Bahereya and Farafra

lacking of any monitoring network. Water quality modelling should be undertaken in

order to forecast the possible deterioration of the water quality related to water use.