Friday, 3 June 2011

Nubian Sandstone Aquifer System - A Water Resource For North Africa

The Guardian recently posted a fascinating article about the Nubian Sandstone Aquifer System (NSAS). The NSAS is a fossil aquifer (i.e. the aquifer formed in the past, storing water, and is not being recharged today - thus it is a non-renewable resource) underlying the countries of Egypt, Chad, Sudan and Libya. The NSAS is believed to hold 150, 000Km3 of water, making it the largest fossil aquifer in the world. Conveniently it is also under one of the driest areas of the world.

Drill Bit
Libya is currently exploiting this resource, and other reserves, to bring fresh water to coastal communities. They are extracting around 2.37km3 a year, feeding it through irrigation systems and bringing it to the coastal communities. There is also exploitation of the aquifer by Egypt. Chad and Sudan are planning to or have only recently begun exploiting the aquifer. The UNDP and other agencies are working closely with the governments of the region to try and ensure the sustainable extraction of this non-renewable resource. Agreements have been made between the four countries to share information and knowledge and work in partnership to access this resource for the benefit of their respective developments. However there are likely to be a number of challenges as a result of this being such a large, transboundary aquifer.

Over the coming years there is likely to be a number of factors that lead to a growing demand for water. An increase in population, rising temperatures, increasing saltwater intrusion in coastal aquifers, and food insecurity could all lead to growing demand for fresh-water for drinking and irrigation. The water resources from the Nubian Aquifer could prove to be a lifeline for these north-east African nations. As this is a transboundary aquifer, there is the potential for conflict over control of the water-supply, although that does not seem to have been the case to date. The unfolding political situation in North Africa could change this, or secure and cement this. 

In addition, the countries must ensure the environmental protection of this aquifer. The potential for contamination in one country to reach another country is not out of the question, especially in the border regions. Strict environmental regulation must be in place in all four countries - again requiring clear dialogue.

Finally, there is the interesting question of what effect will there be on climate and sea-levels from adding an additional 150,000km3 of water into the modern-day water cycle. This is not water that has recently recharged the aquifer, but water that is believed to be around 40,000 years old.

The NSAS is an important and useful resource for global development in North-East Africa. Its sustainable use could lead to successful irrigation projects, and development for the impoverished communities of these countries. However, as the Guardian pointed out, reliance on this aquifer as the principal water source for communities leaves them very vulnerable. The instability of the region means that leaders could (thankfully they haven't yet) shut off the water supply to communities. It is to be hoped  that this resource brings benefit to the people who need it most, and is used in a safe and effective way in order to maximise its lifetime.