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Water is emerging as a significant challenge for mining operations around the world. Nearly two-thirds of mining and metals facilities globally are in regions facing at least one major physical water risk—from drought and flooding to water stress and year-to-year variability in water supply.

Those findings come from the new report called Global Mining and Metals Water Dataset, released by ICMM on July 22, which examined the intersection of physical water risks with 12,000 mining and metals facilities across 148 countries and regions. At a time when the industry is under pressure to expand production of the critical minerals and metals needed for electrification and the energy transition, the report’s findings are particularly significant.

The most prevalent risk identified is baseline water stress, which measures the degree to which total water demand—including industry, agriculture and domestic use—competes with the available water supply. According to the report, 38.2 per cent of mining facilities are located in catchments with high or extremely high water stress, or in arid areas where water is functionally unavailable.

“A basin can have reasonable water supply and still be highly stressed if agriculture, cities, industry and mining are all drawing on it simultaneously, faster than it replenishes,” noted Sally Innis, manager, data and research at ICMM.

In other words, the challenge is not simply finding enough water. Mines share catchments with communities, agriculture and other industries, and the pressure on those shared resources can take very different forms. Companies may need to prepare for acute hazards such as floods and droughts while also contending with longer-term pressures such as competition for water, depletion and unreliable supply.

“The practical consequence is that you can’t assess this from inside the mine fence,” said Innis. “A company managing its own water efficiently can still face significant water risk if the basin it operates in is over-allocated.”

Those risks have implications not only for existing operations but for where and how the industry can grow. Nadja Kunz, an independent academic reviewer of the ICMM report, said water is increasingly important for both existing mines facing climate pressures and for greenfield projects and expansions. “High water risk exposure has the potential to constrain projects from being able to move through into production,” she said.

Part of the problem is that water risks can mean very different things depending on the operation and its surroundings. An operational manager may be concerned about running out of water, said Kunz, while another site may be more vulnerable to flooding. Communities, meanwhile, may be concerned about potential impacts on their water supply or on activities such as fishing. One misconception, she said, is “thinking that water is only an environmental issue.” Taking too narrow a view of the problem can also result in companies looking for a narrow technical solution when the risks—and the expertise required to manage them—may be much broader.

For producers trying to increase output, those considerations are becoming increasingly difficult to separate from mine planning itself. For example, at Vancouver-headquartered Capstone Copper, which has operations in the United States, Mexico and Chile, processing requirements can become more water intensive as operations progress deeper into ore bodies and encounter a greater proportion of sulfide ore compared to oxide ore.

“We therefore recognize that production growth cannot be planned independently from water availability, infrastructure capacity and local watershed conditions,” said Edwin Ruiz, director, tailings and civil infrastructure at Capstone Copper.

The company uses site-wide water balances and scenario analyses that bring together production forecasts, hydrological conditions, available supply and operational demand to identify potential constraints and alternatives earlier in the mine planning process.

Across its operations, the company is also working to improve efficiency and increase its use of recycled and alternative water sources where feasible. Capstone has set a target to reduce freshwater use intensity from 2021 levels by 2030, although progress has not been straightforward. As of 2025, its freshwater use intensity was approximately 30 per cent higher than in 2021; the company attributed this to changing ore mineralogy and processing methods, including a greater share of processing sulfide ores through milling to produce copper concentrate, which is more water-intensive than processing oxide ores through leaching.

Of course, alternative water sources bring their own challenges. They may require significant infrastructure for treatment, conveyance, pumping and storage, while lower-quality water can affect metallurgical recovery or increase corrosion, scaling and treatment needs. Desalination and long-distance pumping can also be energy intensive.

“These constraints mean that alternative sources must be assessed not only for availability, but also for reliability, technical compatibility, environmental implications and life cycle cost,” said Ruiz. “Capstone therefore evaluates the complete water system and applies site-specific solutions instead of assuming that replacing freshwater with another source is sufficient on its own.”

An unpredictable future

Climate change adds another layer of complexity because the water conditions mines have historically planned around may not be the ones they encounter in the future. Kunz said companies need to understand the hazards within their local catchments, examine climate projections and then determine what those changes could actually mean for the business. Increased drought or more intense rainfall, for example, are hazards; the risk depends on how those conditions affect a particular operation.

“When it comes to risk management, it’s also about understanding what that risk poses to the business,” she said, whether that be in financial, production or social terms.

Determining risk has become even more challenging as past conditions are no longer a reliable guide to what will come next. Mines already have to contend with wet and dry periods and year-to-year variability in water availability, and climate change introduces more uncertainty into those projections.

“It’s dangerous for companies to predict the future based on the past only, and not be thinking about how that climate factor can actually change what that probable future scenario is,” said Kunz. Incorporating the best available climate models into site planning, she added, will therefore become increasingly important.

For Canadian miners, the issue is particularly relevant. Kunz pointed to water-related climate risks in Canada, including those associated with permafrost, and said the country needs to take a leading role in climate-resilient water planning. More broadly, she noted that many of mining’s most significant climate-related hazards ultimately manifest through water.

“When it comes to climate hazards, water is really at the forefront of the things that need to be thought about,” she said. “That’s why these two things are often so tightly coupled.”

For mine planners and engineers, preparing for that uncertainty now means designing for a wider range of conditions rather than a single expected future. Ryan Mills, associate vice-president, technical lead—hydrogeology, environment, Canada at AECOM, said conversations about water have changed considerably over the past five to 10 years.

“Mine operators are facing a growing climate paradox: they must be ready for both too little water and too much water, often in the same region,” he said. “As prolonged droughts become more common while rainfall events grow more intense, the design philosophy for mine water management systems and related infrastructure is shifting from relying on historical averages to planning for a wider range of plausible future extremes.”

That shift has practical implications for everything from tailings and water-storage ponds to pumping systems, spillways and treatment facilities. Mills noted that some storage facilities were originally sized using historical precipitation records that may not adequately represent future conditions. Incorporating local climate projections can mean increasing storage capacity and sizing infrastructure to accommodate more extreme rainfall and changing inflows. Drought presents a very different engineering challenge: during low-flow conditions, restrictions on releasing treated water can make adequate storage capacity just as important as treatment capacity itself.

There are limits, however, to what can simply be engineered away, said Sonja Drueke, air quality scientist at AECOM. “In regions where multiple water risks converge, such as drought, flooding, erosion, instability and regulatory constraints, operators must balance infrastructure upgrades with feasibility, prioritizing the most credible high-consequence scenarios and building adaptive capacity where full protection is impractical or economically unviable,” she explained.

Where risks converge

Chile provides a particularly stark example of what can happen when several water pressures converge in a region that is critical to future mineral supply. The country is the world’s largest copper producer and has significant lithium reserves, yet ICMM’s report found that 96 per cent of its mining facilities are in areas exposed to high or extremely high baseline water depletion, while 86 per cent face high baseline water stress and high interannual variability at the same time. “That is the context within which copper and lithium production needs to expand significantly over the next two decades to meet energy transition demand,” said Innis.

For some mining companies, reducing dependence on freshwater has meant turning to the sea. At Capstone’s Mantoverde copper-gold operation in Chile’s Atacama region, desalinated seawater is used alongside water recovered from the mine’s tailings system. Capstone said desalinated seawater at Mantoverde was a major contributor to increasing the proportion of company-wide withdrawals classified as “other water” (water containing total dissolved solids above 1,000 milligrams per litre) from 81 per cent in 2021 to 87 per cent in 2025. The company also intends to use desalinated water at its planned Santo Domingo copper-iron project, which is also in the Atacama region, so that increasing production does not require greater freshwater use.

But rather than eliminating water-supply risk, substituting seawater for freshwater only changes the nature of it. At Mantoverde, reliability depends on the entire system—from the marine intake and desalination plant to energy supply, conveyance, storage, maintenance and contingency planning. According to Ruiz, the operation has strengthened monitoring of maritime conditions to provide earlier warning of events that could disrupt water supply—such as ocean swells or current changes—allowing it to take protective measures and manage available storage.

The best solution may also vary considerably by site. At Capstone’s Mantos Blancos operation in Chile’s Antofagasta region, for example, the company is pursuing treated wastewater as a potential alternative supply in an extremely arid environment, subject to the required infrastructure and approvals.

From efficiency to strategy

The pressure to find those solutions is expected to keep intensifying. A report published by PricewaterhouseCoopers (PWC) in April 2024, called Climate Risks to Nine Key Commodities, mapped the mines responsible for global supplies of several key commodities and modelled their exposure to heat stress and drought through 2050. It found that if the world remains on its current high-emissions trajectory, more than 70 per cent of current copper, cobalt and lithium production could face significant, high or extreme drought risk by mid-century.

Naomi Thomas, a partner in PwC’s sustainability practice, said mining companies are already contending with drought, more intense precipitation events, tightening regulations and growing community pressure around water allocation. “These aren’t distant, long-term risks; they’re outcomes the mining industry is managing today,” she said.

How companies respond is evolving too. “The leaders are moving from water efficiency to water strategy,” said Thomas. She pointed to greater investment in high-rate recycling and tailings dewatering, desalination paired with renewable energy at coastal operations, and dry processing technologies moving from pilot to commercial deployment. These technologies, she said, are not only operational upgrades but are beginning to change the economics of where and how mines can be developed.

That could become increasingly important when companies evaluate new mining projects. “Water access is already one of the variables in project viability, and over the next 10 to 20 years will likely be a defining variable,” said Thomas. Companies that delay incorporating water risk into capital planning, she warned, could find themselves with projects that struggle to reach production or obtain permits.

No mine is an island

Experts say securing a reliable water supply over the long term requires looking beyond the mine site itself. Many water risks originate beyond an operation’s boundaries, which is why they increasingly point to catchment-level planning as an essential part of long-term water security.

Kunz said the industry has already made progress in broadening its perspective. Compared with 20 years ago, when water management was more heavily focused on operational risks within individual sites, she has seen larger mining companies increasingly talk about water stewardship and catchment management. But managing water at that scale can be difficult when responsibility is divided across traditional departmental structures at mining companies. Community concerns identified by social teams, for example, need to feed into production and mine planning, which requires much greater collaboration between disciplines.

That integration needs to extend from individual sites through to corporate decision-making, said Kunz, so that local water risks receive the funding and strategic attention required to address them. Water can also be poorly accounted for across different parts of a business, making it difficult to appreciate its full cost and potential impact on production. Incorporating water into corporate risk registers and decision-making processes can help to ensure it receives the same attention as more immediate production concerns.

The challenge becomes even greater at the watershed level, where mining companies are only one of many users. Aspen Anderson, hydrogeologist at AECOM, said watershed-scale planning and engagement with regulators and other water users can help to identify opportunities to balance mines’ water requirements with broader watershed health. “Treating water as a shared resource rather than simply a permitting requirement ultimately leads to more robust engineering decisions, greater operational flexibility, and more responsible resource development and management,” she said.

In practice, that can mean looking upstream and downstream rather than only at the mine’s footprint. Mills pointed to assessing upstream land use, flood pathways, sediment sources and downstream environmental receptors, while working with communities, Indigenous groups, regulators and other users on shared monitoring, decision-making and coordinated responses to drought or flooding. Such collaboration becomes particularly important where several risks converge and engineering every risk out of the system is neither practical nor economically feasible.

For Innis, one of the barriers to broader-scale planning is that the geography of water does not necessarily align with the way it is governed. “The biggest structural obstacle is that water governance is fragmented across users and jurisdictions, while water risk is at the catchment level,” she said. “A mine can participate in a catchment or basin-level governance process but cannot unilaterally fix an over-allocated basin.”

That makes water security an issue that the mining industry cannot address alone. Asked what single change could most improve the sector’s water security over the coming decade, Innis pointed to governments treating water allocation and mineral development as part of the same planning process. “Integrated land and water use planning is the change that would do the most [to improve water security],” she said.

For mining companies, that makes preparing for future water conditions a considerably broader exercise than just securing enough supply for an individual operation. It is about understanding how climate could alter local hydrology, designing infrastructure capable of handling both water scarcity and excess, investing in alternative sources where they make sense and accounting for the needs and vulnerabilities of the wider watershed.

As demand for critical minerals grows, those considerations will increasingly influence which projects can move forward. As Thomas put it, the question is no longer simply whether a company is managing water effectively today, but whether it is doing enough forward-looking assessment to understand what its operations will need to handle five, 10 or 20 years from now.

For an industry expected to provide substantially more of the critical minerals and metals required for the energy transition, water may increasingly determine not only how mines operate, but where—and how quickly—the next generation of projects can be built.