100 Times More Groundwater In Africa Than Surface Water
April 21, 2012

100 Times More Groundwater In Africa Than Surface Water

Researchers say they have created the most detailed map yet of groundwater across the entire continent of Africa.

A group from the U.K. said they believe there is about 100 times the volume of water underground than there is on the surface of Africa.

The team wrote in the journal Environmental Research Letters that they hope their map can improve access to water in Africa, where 300 million people are said to not have access to safe drinking water.

Helen Bonsor, one of the authors of the paper, told BBC News that she hopes that the new maps will open people's eyes to the potential of having drinking water for people in Africa.

However, the researchers warn that areas with large amounts of water underground will not be found using a scattergun approach.

They said that more careful and exploratory approach will be necessarily in order tap the groundwater below the surface of Africa.

The researchers, from the British Geological Survey and University College London, say that many populated areas in Africa could use hand pumps to obtain the sufficient amount of groundwater that lies below the surface.

They did say opportunities for boreholes, which could bring five liters per second or more, are limited to specific areas like northern Africa.

The team used existing national hydrogeological maps as well as 283 aquifer studies from 152 publications during their research.

They compiled the vast amount of data into a single database, in which the team was able to make their calculations.

According to the study, the amount of groundwater present in certain areas relies on its geological characteristics, such as the amount of weathering and rainfall.

Climate change could pose a huge threat to Africa, as their population continues to explode, yet water resources remain scarce.

However, the team said that groundwater responds more slowly to increasing climatic variability, so it could act as a buffer to climate change.

"Groundwater is such an important water resource in Africa and underpins much of the drinking water supply," Dr Alan MacDonald, lead author of the study, said in a press release. "Appropriately sited and developed boreholes for low yielding rural water supply and hand pumps are likely to be successful and resilient to climate change."

He said that high yielding boreholes should not be developed without having a detailed understanding of the local groundwater conditions.

UK's secretary of state for international development, Andrew Mitchell, told BBC reporter Matt McGrath that he welcomed the latest study.

"This is an important discovery," he told BBC. "This research, which the British Government has funded, could have a profound effect on some of the world's poorest people, helping them become less vulnerable to drought and to adapt to the impact of climate change."