Southern Africa is one of the areas of the world most affected by drought. In the SeeKaquA project, the international research team led by the LIAG Institute for Applied Geophysics (LIAG) aims to detect deep groundwater resources in the Kalahari using state-of-the-art drone-based electromagnetics. The University of Namibia (Namibia), the University of Zambia (Zambia), the SADC Groundwater Management Institute (South Africa), the Federal Institute for Geosciences and Natural Resources (Germany) and the company terratec Geophysical Services (Germany) are also involved in the project. It is being funded by the German Federal Ministry of Education and Research (BMBF) with 1.3 million €.

Why is the development of new groundwater resources at greater depths so important?

Water resources on the earth’s surface are particularly sensitive to seasonal variations in precipitation and are prone to contamination. To improve the long-term water supply, the development of new groundwater resources at greater depths is of crucial importance, especially in times of climate change. In the SeeKaquA project, African and German scientists are exploring these resources in an effort to develop strategies for sustainable water management in Namibia and Zambia. At the same time, they aim to ensure a continuous transfer of knowledge and technology to the region.

Innovative measuring techniques

Ground-based electromagnetic methods have been used in geophysics for decades for groundwater exploration. The electrical conductivity of the subsurface can be derived from the measurements as an indicator of water-bearing layers or salinization zones. SeeKaquA employs semi-airborne electromagnetics, an innovative new measuring technique. It combines few power sources installed on the ground with highly sensitive magnetic field sensors, which are transported through the air with the help of drones. This method makes it possible to map underground structures over areas of several square kilometers in a cost-efficient and environment-friendly way, which allows a detailed analysis of aquifers down to a depth of several hundred meters. The geophysical results provide important data for hydrogeological interpretation and modelling in order to make recommendations for suitable drilling locations. Thus, they increase the chances of success of comparatively expensive boreholes for groundwater extraction.

“Sustainable groundwater management that also takes into account deep groundwater reservoirs in addition to the shallow reservoirs that have only been used so far can make a valuable contribution to climate resilience, especially in the climate conditions in southern Africa,” explains Dr Raphael Rochlitz, project leader and scientist at LIAG.

Transfer of knowledge also in foreground

The joint project is funded by the BMBF as part of the German-African WASA research program. The goal is to contribute to new solutions for the sustainable improvement of water security in Africa.The first in-person meeting between the partners took place at the end of September 2024 in Stellenbosch, South Africa, as part of the WASA kick-off conference. It marked the start of the intensive collaboration. Several measurement campaigns will start from spring 2025.

A central component of the project is also the transfer of knowledge to local universities, companies and authorities in southern Africa. This includes training courses, workshops and the provision of open-source software for geophysical data processing.

Further information is available on the project website.