More Critical Minerals Mining Could Strain Water Supplies in Stressed Regions

Demand for critical minerals is booming. Global efforts to fight climate change are driving up the need for lithium, cobalt, graphite and other such minerals essential for building electric vehicles, solar panels and other clean technologies. This compounds existing demand from the tech sector, where critical minerals are used in smartphones, laptops and other consumer electronics.

There’s no question the world will have to mine more of these minerals, and quickly, as the clean energy transition ramps up. But doing so also comes with risks — including the potential to sap water supplies.

Using global data from the U.S. Geological Survey (USGS) and WRI’s Aqueduct tool, we found that at least 16% of the world’s land-based critical mineral mines, deposits and districts are located in areas already facing high or extremely high levels of water stress. These are areas where agriculture, industry and households regularly use up much or most of the available water supply. Without proper management, critical minerals mining can be extremely water intensive and polluting, further straining limited freshwater supplies.

Critical Minerals Mining Depletes and Contaminates Fresh Water

Most methods used to mine critical minerals today require significant amounts of water for separating minerals, cooling machinery and controlling dust. Waste from mining and processing, including residual minerals and chemicals, can also contaminate water in nearby communities.

Current processes for extracting lithium — a critical mineral used in both electric vehicle (EV) batteries and solar panels — are particularly water-intensive. Take the “lithium triangle” in South America. This area spanning parts of Chile, Argentina and Bolivia contains over half the global lithium supply, found in brine pools underneath the region’s vast salt flats. Miners pump this brine into large pools on the surface of the flats, where the water evaporates out and leaves behind lithium carbonate, used for producing clean energy technologies.

This evaporation method uses up to half a million gallons of brine water to extract one ton of lithium. While the brine water itself is unfit for drinking or agricultural use, some reports show that withdrawing such large quantities can cause fresh water to flow into brine aquifers and mix with salt water. This can result in salinization of fresh water and deplete nearby surface and groundwater supplies.

In Chile’s Salar de Atacama, one of the country’s key mining regions, lithium and copper extraction have reportedly consumed over 65% of the local water supply, depleting available water for Indigenous farming communities in an already water-scarce region. Indigenous communities in Chile and Argentina have also reported contamination of fresh water used for drinking, livestock and agriculture with toxic waste from lithium operations.

Impacts to fresh water are not unique to Chile nor to the lithium industry; they are occurring across global mining and processing locations for a variety of critical minerals. Similar concerns about water use and contamination have already been reported for cobalt in the Democratic Republic of Congo (DRC) and graphite in China, among others.

Increased Mining Could Make Already Water-stressed Areas More Vulnerable

The USGS’s Global Distribution of Selected Mines, Deposits, And Districts Of Critical Minerals data set, last updated in 2017, spans 116 countries. An analysis of data from USGS and WRI’s Aqueduct Water Risk Atlas reveals that at least 16% of the global critical mineral mines, deposits and districts located on land are in areas facing high or extremely high baseline water stress. In these locations, at least 40% of the water supply is required each year to meet existing demand, meaning that there is high competition for water among agricultural, industrial and domestic users and sometimes not enough water left over to sustain important freshwater ecosystems.

A further 8% of global critical mineral locations are in arid and low-water-use areas, where available water supplies and total water demand are very low. Rapid increases in mining activity in these regions could easily increase demand for water and push these locations with already-scarce freshwater supplies into high or extremely high levels of water stress.

Arid, low-water use and/or highly water-stressed countries with the most critical minerals sites include the United States, Australia, South Africa, India, China, Mongolia, Russia, Mexico, Chile and Namibia.

Research also shows that water stress is rising in many areas of the world. Under a business-as-usual scenario, the percentage of today’s critical mineral locations that would be located in areas of high or extremely high water stress would increase to 20% by 2050. And while the USGS data is the best publicly available data set of global critical minerals locations, it is most robust for U.S. sites and excludes copper, another mineral used in many renewable energy technologies. More comprehensive data could show an even greater overlap between critical minerals sites and water stress.

Better Water Management Is Essential

Important efforts are underway to reduce demand for new critical minerals through reuse and recycling and increasing public transportation (as opposed to relying primarily on private EVs). But these options are still nascent. The world will certainly have to increase mining operations in the near-term to build an adequate mineral supply chain for the clean energy transition.

Without proper precautions, these efforts could come with serious side effects in communities located near critical mineral mines and processing facilities. So it’s crucial that governments and companies along the value chain take steps to better measure and manage the water-related risks associated with critical minerals.

Water-management techniques could include:

1) Explore new technologies to reduce mining’s impacts on water.

Several mining companies are exploring new methods, such as direct lithium extraction (DLE), to reduce the water-related risks of mining. Unlike the evaporation process, DLE captures usable forms of the mineral directly from brine water, reducing water usage and decreasing the potential for toxic waste to leak from evaporation pools into water supplies. It may also increase the recovery rate of lithium from brine, reducing environmental impacts while boosting production.

Some start-ups are also developing new microbial technologies to remove harmful toxins from mining waste and enable wastewater to be reused at mining sites. This can reduce overall water use in critical mineral mining and limit potential contamination of clean water.

However, many of these technologies are still nascent and have not yet been implemented on a commercial scale. Further studies by researchers, engineers and the scientific community are needed to better understand their impacts, in addition to more investment in research and development.

2) Assess water risks across companies’ value chains and set ambitious water targets.

Growing media attention as well as complaints from local communities have prompted some companies to begin addressing water-related risks in the critical minerals industry. Setting contextual water targets is one way companies can respond to water challenges along their value chains.

Several mining companies have already set water targets for their operations. These are mainly focused on reducing water use, such as by repairing leaks and reusing treated wastewater. For example, Sociedad Química y Minera de Chile (SQM), one of the world’s largest lithium producers, committed to reduce water use in its lithium mining by 65% by 2040 and cut brine extraction by 50% by 2028. Glencore, the largest cobalt mining company, has used Aqueduct data to set contextual water targets addressing water usage and access in its water-stressed sites.

However, companies need to look beyond water usage within their own facilities and also consider the surrounding watershed. Efforts should address not only water quantity issues, but also water quality and other challenges. Actions could include implementing nature-based solutions, such as restoring wetlands and forests to recharge groundwater, mitigate flood risk and improve water quality.

Companies further downstream in the value chain, such as technology companies and EV manufacturers, should also consider the water impacts of critical minerals in their supply chains when setting contextual water targets and stewardship strategies.

3) Improve governance and environmental regulation.

Voluntary corporate initiatives are not enough to combat water challenges; governments also need to take action. Poor oversight and regulation can exacerbate water-related issues and other environmental and social risks related to mining. Yet high volumes of critical minerals such as copper, lithium, nickel and cobalt are produced in regions with low governance scores.

Better governance is especially important for artisanal and small-scale mining operations, which tend to be rife with environmental and safety hazards. Although this type of mining is often illegal, it's not uncommon: It accounts for 15%-30% of cobalt produced in the Democratic Republic of Congo, which provides 70% of the world’s supply.

While many countries enforce environmental standards in the private sector, few have developed mining-specific regulations. Existing guidance from multi-stakeholder efforts and industry organizations such as IRMA and ICMM can serve as a starting point for local and national governments to develop robust regulations around water use, discharge and waste management. Decision-making must also include local communities and Indigenous Peoples, with mechanisms for these groups to voice concerns throughout the permitting and planning stages and beyond.

At the international level, countries including the U.S., Australia and Canada have partnered to strengthen responsible mining, processing and recycling of critical minerals through the Minerals Security Partnership and the Energy Resource Governance Initiative. By sharing best practices, improving transparency and attracting investment, these partnerships have the potential to bolster environmental governance worldwide — especially in countries where local and national regulatory capacity is low and where artisanal and small-scale mining is prevalent.

4) Expand access to data about mining’s impacts.

Few mining companies publish data on water use and water quality at critical mineral sites. Public data on mining and processing locations is also lacking. In addition, most companies source critical minerals from third-party smelters and refiners and may not know where the minerals in their products were mined. These data gaps limit governments’ ability to set effective water policies and companies’ capacity to set robust water targets along their value chains.

One major effort to improve transparency in critical minerals sourcing — the Global Battery Alliance (GBA) Battery Passport — aims to collect and report data on the make-up, manufacturing history and sustainability of a battery across its lifecycle. Including information on water risks or impacts in this and other supply chain data initiatives could help.

Governments can also set clear and consistent reporting requirements for the mining sector. Mining companies should be required to report on site-level water sources, use and discharge, as well as any certifications in place. One example is SQM’s publicly available online monitoring platform.

In the meantime, downstream companies can use available data and guidance to begin assessing upstream risks from critical mineral mining and processing. For example, the Organization for Economic Co-operation and Development recently published a Handbook on Environmental Due Diligence in Mineral Supply Chains, which encourages companies to collaborate with known suppliers to provide more visibility into minerals’ origins.

Increased Critical Minerals Mining Must Go Hand-in-Hand with Better Water Management

Building enough low-carbon technology to avert the worst impacts of global warming will require more extraction and processing of critical minerals — there’s no way around it. But as production scales up worldwide, water management cannot be an afterthought.

Governments, companies and NGOs must work together to improve tracking and develop technologies, regulations and stewardship strategies that protect the world’s freshwater while simultaneously ushering in more clean energy.