Lithium and Water: Understanding the Environmental Debate in the Puna

Why water is at the center of the debate

Lithium extraction from brines is today the dominant method in Argentina and across the Lithium Triangle it shares with Chile and Bolivia. The traditional approach involves pumping brine from underground aquifers beneath the salt flats and concentrating it in large evaporation ponds, taking advantage of solar radiation and the dryness of the Puna. This process, efficient and low-cost, requires time and, above all, water: both the brine itself and the freshwater used in processing and purification stages.

The environmental debate stems precisely from this point. The Puna is one of the most arid regions on the planet, where water is a scarce and contested resource. Any activity that uses it in large volumes raises, rightly, legitimate questions from communities, provincial governments, and investors assessing long-term risks.

How much water is actually used

It is worth distinguishing between two types of water. Brine is a saline fluid, unfit for human consumption or agriculture, extracted from the subsoil of the salt flat. Freshwater, by contrast, comes from surface sources or freshwater aquifers and is used in smaller proportions for industrial processes. According to sector estimates, conventional evaporation projects can consume between 100 and 800 cubic meters of freshwater per ton of lithium carbonate equivalent, with enormous variability depending on the technology and brine quality.

Brine consumption is much larger in volume, but the focus of scientific concern lies in the water balance of the system. Salt flats function as closed basins where brine and freshwater coexist in a delicate equilibrium. Extracting brine at a rate higher than its natural recharge can, in theory, alter the interfaces between freshwater and saltwater, affecting wetlands, meadows, and high-altitude lagoons that sustain biodiversity and the life of communities.

The impact on salt flats and communities

Salt flats are not dead environments. They host fragile ecosystems, with flamingos, unique microorganisms, and wetlands that depend on water to survive. The indigenous communities of the Puna—Kolla and Atacama, among others—maintain activities such as herding and subsistence farming that require access to water. For this reason, rigorous hydrogeological monitoring and the participation of these communities in decision-making are indispensable conditions for socially acceptable mining.

The available evidence is nuanced. Some studies point to declines in water table levels near intensive operations, while others indicate that, with well-calibrated extraction plans and solid baselines, the impact can be kept within manageable margins. The key lies in the quality of the data and the independence of monitoring, rather than in condemning or defending the activity in the abstract.

DLE as a technological response

Direct lithium extraction (DLE) is emerging as the main bet to reduce the water footprint. Unlike evaporation, which takes months and releases the brine's water into the atmosphere, DLE uses selective processes—adsorption, ion exchange, or membranes—to capture lithium directly and reinject much of the depleted brine into the aquifer.

The potential advantages are significant: faster production, better lithium recovery rates, and, above all, the ability to recycle a large portion of the water used. Some DLE technologies promise to recover and reuse between 70% and 90% of process water. However, it is not a magic solution: several variants consume more energy and, in certain cases, require additional freshwater. Technological maturity at industrial scale is still consolidating.

Toward a possible balance

The real challenge is not choosing between producing lithium or protecting water, but integrating both objectives. This requires robust hydrogeological baselines before operations begin, continuous and transparent monitoring, extraction limits adjusted to the real recharge of each salt flat, and genuine consultation mechanisms with communities. Water governance, more than technology itself, is often the decisive factor.

Regulatory frameworks and international sustainability standards, increasingly demanded by buyers and financiers, push in that direction. A project with good water performance not only reduces its environmental risk: it also improves its access to capital and its social license to operate.

The Argentine case: opportunity and responsibility

Argentina, the world's fifth-largest lithium producer and with extraordinary growth potential in the Puna of Jujuy, Salta, and Catamarca, has much of its credibility at stake in this area. The RIGI, in force since 2024, attracts large-scale investments, but its long-term success will depend on these projects demonstrating rigorous and verifiable water management.

The gradual incorporation of DLE, combined with more demanding provincial regulations and community participation, offers a path for Argentina's lithium development to be both competitive and environmentally defensible. The balance between production and water is not an obstacle for the industry: it is, increasingly, the very condition of its viability in the Puna.