SeeKaquA

The SeeKaquA project strives to improve exploration techniques for deep groundwater in the Kalahari Basin, which spreads through the Central Southern African region for sustainable water supply.

Dr. Josefina Hamutoko

The focus of the project is on the transfer of knowledge and technology. We believe that this can increase the development of groundwater in southern Africa beyond the scope of this project.

Dr. Roland Bäumle

Abstract

Arid regions in Southern Africa, which currently depend on surface water resources, experience severe challenges to supply clean water in times of continuously growing water demands and climate change. The SeeKaquA project aims at exploring two different deep aquifer systems in Southern Africa to make these water resources available for sustainable water management. For this purpose, we consider the environmental friendly semi-airborne electromagnetic (SAEM) method with unique capabilities to provide large-scale 3D models of the electrical conductivity in the subsurface to enhance the hydrogeological understanding at two demonstration sites, the Cuvelai-Etosha Basin (CEB) in Namibia and the Machile-Zambesi Basin (MZB) in Zambia. Groundwater sampling from existing boreholes will further support the interpretation of the geophysical measurements. Integrating all collected data with existing geological, hydrochemical and borehole information in hydrogeological modeling will provide recommendations for drilling locations and an estimate of the potential value of groundwater in the pilot regions that can contribute to a sustainable water management plan. 

Impact

Our project can improve the water supply in the Southern African region while contributing also to climate resilience with the potential exploitation of deep groundwater instead of surface water resources. A sustainable knowledge and technology transfer of the SAEM method in combination with the hydrogeological analysis is a major goal of SeeKaquA. We aim to achieve it by working together in an international consortium of research institutions in Africa and Germany and the geophysical exploration company terratec with local branch offices in Namibia and Germany. The close cooperation of academic and industrial partners as well as local stakeholders as associated partners aims to enable not only the first successful demonstration of applying the SAEM method for groundwater exploration during the project phase, but also independent exploration activities in the long term. The applied workflows to identify deep groundwater resources and to recommend suited drilling locations have a high potential to be transferred to other regions in Southern Africa and worldwide. 

Proposed study areas

Focal points of the project 

• First application of the SAEM method supporting hydrogeological interpretation of deep aquifer systems 
• Improvement of SAEM measurement system to be modular with state-of-the-art components
• Enhancement of processing and inversion software with focus on groundwater applications and modern open-source implementation to provide accessibility worldwide  
• Hydrogeological modeling including 3D resistivity information to recommend suited drilling locations 
• Recommendations for use of deep groundwater resources as part of a sustainable groundwater management  
• Knowledge and technology transfer to local stakeholders such as companies, universities, and authorities for long-term exploitation of the developed workflows

WP 1: Cuvelai-Etosha Basin demonstration site (Namibia) 

Lead partners: LIAG, terratec, BGR, UNAM 

We will perform the first field campaign lasting three weeks at the CEB demonstration site in the second project year. We are confident to cover multiple square kilometres with SAEM data to provide a detailed 3D resistivity model after processing and inversion of the obtained raw data. This model can enhance our understanding of the current salinity distribution within the KOH-II aquifer and provides valuable insights into the hydrogeomorphological features frequently observed in alluvial depositional environments. To complement the geophysical and other existing information, we will collect additional hydrogeological information in the field as part of groundwater sampling and monitoring campaigns. Laboratory experiments including batch tests, column experiments and sand tanks will further support the understanding of geochemical processes in the subsurface. The ultimate goal is to have a hydrogeological model of the local site available to develop recommendations for managing the regional water supply in the upcoming years. 

WP 2: Machile-Zambezi Basin demonstration site (Zambia) 

Lead partners: LIAG, terratec, BGR, UNZA 

The second field campaign at the MZB demonstration site is scheduled in the third project year. The workflows are comparable to WP 1, though there are less hydrogeological information and no borehole data available at this demonstration site. Therefore, the primary focus here is to explore poorly known freshwater resources in the deeper subsurface based on the obtained 3D resistivity models. This site is particularly suited to show that the modern SAEM exploration method with dense data coverage can provide subsurface models which are detailed enough to identify optimum drilling locations for potential groundwater exploitation. 

WP 3: Knowledge and technology transfer 

Lead partners: LIAG, BGR, SADC-GMI 

In the first months of the project, LIAG and terratec assemble a new modularized SAEM measurement system for the usage in SeeKaquA and beyond. SADC-GMI acquires and installs a workstation with support from LIAG. It allows the African partners to perform resource-demanding simulations including geophysical as well as hydrogeological modeling, processing, and inversion. During the second half of the first year, we invite the African partners for an initial training workshop in Germany and organize a practical training and initial operation of the new measurement system in Namibia. During the measurement campaigns at the demonstration sites and the subsequent data analysis, we aim to transfer enough knowledge by on-the-job-training to allow independent usage of the applied methods by the African partners after the project phase. The outcomes of our activities and the potential to apply our exploration strategy in other regions will be presented to a broad audience of interested local stakeholders at a final workshop held in Southern Africa. In this way, knowledge and technology transfer is promoted throughout the entire project.