With water constraints tightening across Africa and climate variability placing new pressures on mine infrastructure, mining operations can rely on water balance modelling to improve planning and reduce risk.
With regulators, investors and financial institutions adopting stricter expectations around water use, mines are under growing pressure to demonstrate transparent and responsible water management
According to SRK Consulting South Africa senior hydrologist Simon Bruton, mines that understand their water systems in detail are the ones best positioned to manage costs, support compliance and design resilient infrastructure.
“A water balance sits at the centre of designing the right infrastructure, managing environmental risk and ensuring long-term efficiency,” Bruton argues. “You can’t manage water properly if you don’t measure and model it.”
A water balance accounts for water flow entering or leaving a site, whether through rainfall, groundwater, run-off, evaporation, piping networks or storage facilities. In the mining sector – where operations may span hundreds of hectares and incorporate multiple water systems – these balances become critical tools for understanding both present conditions and future requirements.
SRK Consulting South Africa senior hydrologist Simon Bruton
Designing the right infrastructure
Bruton highlights that water balances play a pivotal role long before construction begins.
“A well-built water balance allows us to test whether proposed storage dams, stormwater channels, pipelines or pumping systems can really handle the volumes they will face,” he explains. “This becomes even more important when mines are expanding production or rethinking their water management strategies.”
Most water flows can be measured directly, he points out, but others – such as rainfall contributions and catchment run-off – must be simulated. This combination of field data and modelling gives hydrologists a complete view of how water moves through a mining site.
“When we build a water balance, we often find gaps in monitoring networks or discover losses the mine didn’t know about or are unable to measure,” Bruton notes. “The balance becomes a diagnostic tool. It highlights where instrumentation needs to be upgraded, and it often reveals hidden inefficiencies or unnecessary water losses.”
Such insights can help mining teams avoid oversizing infrastructure or misallocating capital to systems that will not meet long-term requirements.
Forecasting for climate, production changes
Beyond understanding current conditions, forecasting is where water balances bring major value to infrastructure planning. Mines can simulate the impacts of higher production rates, new or expanded facilities, altered water recycling strategies or additional storage demands.
“Forecasting lets us stress-test the system,” he says. “We can see what would happen in a drought or during an extreme rainfall event, or when climate change shifts the seasonal distribution of rainfall. With all that information, mines can make informed decisions instead of reacting in crisis.”
Climate-linked modelling is increasingly important for mines across Africa, as some regions may see reduced annual rainfall but more intense storm events – while others may face longer dry spells.
“Even if annual rainfall appears stable on paper, climate predictions show that the timing and intensity could change dramatically,” he explains. “That directly affects storage sizing, spillway design and the security of supply.”
Stochastic modelling – using multiple simulated climate or rainfall scenarios – helps quantify risk in statistical terms. Mines can then weigh risk against capital costs and decide what level of security is financially acceptable.
“This is where the water balance becomes a decision-support tool,” says Bruton. “It helps mines evaluate the trade-off between infrastructure costs and operational risk.”
Water stewardship, smarter compliance
With regulators, investors and financial institutions adopting stricter expectations around water use, mines are under growing pressure to demonstrate transparent and responsible water management. An accurate water balance is often central to these requirements.
“Authorities expect detailed reports on how much water a mine is using across various categories, how efficiently the water is recycled and how responsibly wastewater is managed,” he explains. “A calibrated water balance provides that level of valuable detail.”
Automated reporting systems derived from water balance models can feed daily, weekly or monthly dashboards for operational staff. These systems also support licensing, environmental authorisations and industry accreditation programmes, where water stewardship is becoming a prerequisite for maintaining social licence and investor confidence.
A water balance accounts for water flow entering or leaving a site, whether through rainfall, groundwater, run-off, evaporation, piping networks or storage facilities.
Improved efficiency, lower costs
The financial benefits of water balances are significant. As climate change causes shifts to extreme rainfall events, the cost of storage infrastructure to contain these extreme events escalates. Additionally, a water tariffs rise and energy-intensive pumping becomes more expensive, identifying opportunities for water reuse or reducing treatment volumes can translate directly into savings, Bruton notes.
“A good water balance often pays for itself,” he says. “By highlighting inefficiencies, modelling recycling scenarios or reducing the need for oversized storage, mines can save substantial amounts – not just on water, but on the electricity and infrastructure required to handle it.”
In many cases, water balances can highlight and test opportunities to incorporate lower-cost, nature-based solutions, says Bruton. These may include infiltration structures, flood retention basins or landscape-based dispersal systems that reduce reliance on costly traditional stormwater retention and storage structures.
