Sulzer South Africa Managing Director Henry Kraukampf reflects on the critical importance of groundwater management in mines across sub-Saharan Africa.
The Mponeng gold mine in South Africa lies approximately 4 km below the surface and holds the title of the deepest gold mine in the world. Remarkably, six of the ten deepest mines in the world are located in Gauteng alone. However, complexity increases with increasing depth, and one of the most pressing challenges in these operations is water management. This is particularly true across sub-Saharan Africa, where difficult natural conditions amplify risks. For example, Zambia’s copper mines are among the wettest in the world.
Effective groundwater management under these conditions requires more than just equipment. It requires long-term planning, community partnerships and a lifecycle approach beyond the life of the mine to reduce risks to the local environment.
Multi-layered water risks below the surface
Deep mines in sub-Saharan Africa often face water ingress from two directions. Surface water descends through the shaft and groundwater rises from below. If not properly controlled, these levels can quickly overwhelm operations. If a dewatering pump fails, an entire mine level or even the entire mine can become inaccessible within a few days. The deeper the mine, the higher the risk.
But the challenge doesn’t end when production stops. Many of the region’s mines are located in semi-arid regions with low water tables. If uncontrolled, over time, groundwater can migrate upward through cracks created by mining activities. When this water (often acidic and contaminated with heavy metals) enters the aquifer, it can have serious environmental impacts.
An alarming example is in the US state of Colorado, where about 500 of the state’s 23,000 abandoned mines are polluting more than 1,800 rivers. This is a stark reminder of the long-term impacts of unmanaged groundwater and the need for pre-emptive action to avoid similar outcomes in Africa.
A life cycle approach to groundwater management
Mitigating these risks starts with an overall long-term plan. Groundwater management must be integrated into the mine design and operations strategy and should not be treated as a secondary issue. This includes implementing durable pumping solutions that can withstand corrosive acidic water while maintaining high performance over long periods of time.
Close collaboration with local partners and service teams is essential. They not only help operators select and install the right equipment, but also provide important ongoing monitoring and maintenance. Pumps operating in harsh groundwater conditions are subject to wear and tear and, if not properly maintained, reduce efficiency and increase the risk of failure.
Fortunately, early detection of performance issues allows for minor refurbishments that can significantly extend pump life from the industry average of 10,000 hours to up to 45,000 hours. The economic benefits are significant, with increased efficiency saving thousands of dollars per pump per year, while inefficient pumps can cost operators hundreds of thousands of dollars in excess energy usage alone.
Transition from reactive to predictive operations
Given the harsh realities of mining in sub-Saharan Africa, a reactive approach to groundwater management is no longer viable. Proactive partnerships with local OEMs with engineering capabilities and field service experts enable preventive and predictive maintenance, reducing the risk of downtime and ensuring issues are addressed before they become serious.
In the event of a failure, local support becomes even more important. Local teams can respond quickly to carry out critical renovations and minimize downtime. This is a capability that is often not possible with remote providers.
By planning for groundwater issues from day one and maintaining that focus throughout the mine lifecycle, operators can protect assets, reduce operating costs, and minimize environmental impact. In doing so, we lay the foundation not only for operational success but also for long-term sustainability.
The article is available online: https://www.globalminingreview.com/mining/10102025/managing-groundwater-in-the-worlds-deepest-mines-a-strategic-imperative-for-sub-saharan-africa/
