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Scientists Uncover Groundwater in the Sahel

2017/04/27

In the deserts of the Sahel, one of the poorest regions of the world, rich bodies of water underground provide a source of life.

The Sahel stretches from western Africa to central and northern Africa and is home to 135?million people. One of the biggest challenges in the region is access to clean water, for drinking, food production and sanitation.

Using nuclear-derived techniques, scientists from 13?African countries have carried out the first ever regionwide assessment of groundwater in this area of 5?million square kilometres, with the help of the IAEA.

Through its technical cooperation programme, the IAEA has provided equipment and trained scientists from 13?countries — Algeria, Benin, Burkina Faso, Cameroon, Central African Republic, Chad, Ghana, Mali, Mauritania, Niger, Nigeria, Senegal and Togo.<br><br> Scientists have been studying five main aquifer systems that cross their borders: the Iullemeden aquifer system, the Liptako-Gourma-Upper Volta system, and the Senegalo-Mauritanian, Chad and Taoudeni basins.<br><br> The spots on this map show where scientists collected water samples.

Over the past five years, scientists have collected almost 2000 samples from wells, rivers and rain in the region’s most populated, often cross-border areas.

IAEA experts have helped them analyse these samples, using isotopic and other chemical parameters. They also helped in the interpretation of the data.

Studying the different isotopes present in water helps determine the source, age, recharge flow and quality of the groundwater.

So far, scientists from each country have published major findings, which include recommendations for governments to draw up plans to save water and protect the groundwater from pollution.

The next step will be to integrate these findings and publish a comprehensive report that will summarize all the information of groundwater availability and quality across this vast region and identify common threats.

The report’s recommendations, if implemented, are expected to enhance the sustainable management and use of the shared aquifer systems and reduce the impact of pollution on water quality.<br><br> Photos and captions: Laura Gil/IAEA

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