First map of groundwater recharge in Africa will help sustain water supplies

Tuesday, 16 February 2021

Researchers have provided the first ever map of the rate groundwater reserves are being replenished across Africa based on ground measurements. This shows that groundwater is being replenished at rates that could help to protect and sustain water supplies against the effects of climate change.

In Africa the groundwater, stored in rocks, is central to the water and food security of many communities. The rate at which groundwater is recharged is a key factor determining the sustainability of this resource, but until now there has been no continental-scale mapping of recharge rate across Africa.

An international team of scientists from the British Geological Survey, University of Nottingham and universities in South Africa, Nigeria and the US, have published new research in Environmental Research Letters that provides the first ever map of the rate of groundwater recharge across Africa based on field observations.

The scientists mapped average groundwater recharge rates for the whole of Africa from 1970 to 2019, comparing results from over 134 separate studies and then combining it with data about available groundwater storage.

The findings of the study give a positive message about the sustainability of groundwater in Africa where it is increasingly being used as a reliable source of drinking water and irrigation. The research estimates that the long-term groundwater recharge in Africa is approximately 15,000 km3 (cubic km) per decade and that recharge can occur even in arid and semi-arid areas. This is equivalent to more than half the annual rainfall in Africa, which is replenishing the groundwater every decade.

It was very exciting to see the story about recharge rates and their variation across Africa emerge from the analysis of many different sources of data which colleagues had painstakingly assembled. Groundwater is key to so many of the Sustainable Development Goals, and quantifying the behaviour of a natural resource is an essential part of protecting and sustaining it.
Professor Murray Lark from University of Nottingham's Future Food Beacon undertook the statistical modelling for this research, using approaches developed over recent years to assess complex sources of variation in spatial data.

BGS Hydrogeologist, Prof Alan MacDonald, is lead author of the paper based at The Lyell Centre in Edinburgh and has led multiple studies on groundwater in Africa over the last two decades.

He said: “The data reveal some interesting patterns about Africa’s water security. We already know that having both low groundwater storage and recharge considerably reduces water security for local populations.

“What these new maps tell us is that the majority of African countries have either high storage, or high groundwater recharge.

“This is important because it provides essential insight into how Africa benefits from the distribution of groundwater storage and recharge.

“It shows where there is potential to sustainability develop more groundwater and also highlights where efforts should be targeted to carefully monitor groundwater supplies vulnerable to drought.”

Professor Lark leads the CEPHaS project, supported by the UK's Global Challenges Research Fund. CEPHaS is a collaboration with institutions in the UK, Zimbabwe, Zambia and Malawi, which examines the impacts of conservation agriculture practices on the water cycle, and the implications for food and water security.

The maps will be added to the online groundwater Atlas, which provides a publicly available gateway for groundwater information in African countries.


Story credits

More information is available from Professor Murray Lark on or Jane Icke, Media Relations Manager for the Faculty of Science at the University of Nottingham, on +44 (0)115 951 5751,

Jane Icke - Media Relations Manager Science
Phone: 0115 7486462

Notes to editors:

The University of Nottingham

Our academics can now be interviewed for broadcast via our Media Hub, which offers a Quicklink fixed camera and ISDN line facilities at Jubilee campus. For further information please contact a member of the Press Office on +44 (0)115 951 5798, email

For up to the minute media alerts, follow us on Twitter

The University of Nottingham is a research-intensive university with a proud heritage. Studying at the University of Nottingham is a life-changing experience, and we pride ourselves on unlocking the potential of our students. We have a pioneering spirit, expressed in the vision of our founder Sir Jesse Boot, which has seen us lead the way in establishing campuses in China and Malaysia - part of a globally connected network of education, research and industrial engagement. Ranked 18th in the UK by the QS World University Rankings 2023, the University’s state-of-the-art facilities and inclusive and disability sport provision is reflected in its crowning as The Times and Sunday Times Good University Guide Sports University of the Year twice in three years, most recently in 2021. We are ranked seventh for research power in the UK according to REF 2021. We have six beacons of research excellence helping to transform lives and change the world; we are also a major employer and industry partner - locally and globally. Alongside Nottingham Trent University, we lead the Universities for Nottingham initiative, a pioneering collaboration which brings together the combined strength and civic missions of Nottingham’s two world-class universities and is working with local communities and partners to aid recovery and renewal following the COVID-19 pandemic.

More news…

Media Relations - External Relations

The University of Nottingham
C Floor, Pope Building (Room C4)
University Park
Nottingham, NG7 2RD

telephone: +44 (0) 115 951 5798