A Desert Where the Taps Still Run

In the far north of Chile, the Atacama Desert stretches under a relentless sun. Some towns in the region have not seen rainfall in over ten years. Yet in Antofagasta, a port city in Northern Chile, water still flows from the taps. It does not come from rivers or reservoirs. It comes from the sea. 

Between 2022 and 2025, Chile redefined its national water strategy. What began as isolated pilots in desalination and water reuse has matured into a country-wide transformation. Backed by legal reform, public investment, and private innovation, Chile is reshaping how a nation survives under water stress. 

The Crisis That Forced a Reckoning

Chile’s transformation was born out of crisis. Over the past 15 years, an unrelenting megadrought has pushed the country to its limits. Water availability has declined sharply. Between 2009 and 2022, national surface water availability dropped nearly 20 percent (OECD, 2024). In the agricultural heartland of Coquimbo, crop failures mounted as irrigation channels ran dry. In Santiago, the nation’s capital, water alerts were issued in both 2021 and 2022, signaling shortages for millions.

It became clear that traditional water management – relying on glacial melt and seasonal rainfall – could no longer sustain the country. Chile needed new sources of water, and it needed them quickly.

Mining Moved First

The mining sector led the initial response. Copper, which represents more than half of Chile’s export value, is concentrated in the arid north. Companies like BHP, Codelco, and Antofagasta Minerals had already begun investing in desalination before 2022. To safeguard their operations, some mines, including Escondida, began using untreated seawater directly in mineral processing, reducing freshwater withdrawal to zero.

In March 2024, Antofagasta Minerals opened a $2 billion desalination plant at Los Pelambres mine in Coquimbo. Built by Bechtel, the facility produces 400 liters per second and is expected to double capacity by 2027. According to COCHILCO (2024), desalinated or reused water already meets 40 percent of northern mining demand, up from 25 percent in 2020. That figure is projected to exceed 65 percent by 2032.

Small Towns, Big Lessons

In Coquimbo, the drought’s impact was deeply personal. Fields once green with alfalfa turned to dust. But in towns like Cerrillos de Tamaya, local innovation began to reverse the trend. With support from Fundación Chile, small wastewater treatment plants were retrofitted to supply water for irrigation. The water, while not potable, sustained farms that would have otherwise failed.

“Without the treated water, my fields would’ve dried up completely,” farmer Jorge Ramírez told Inter Press Service in 2023. These small projects, delivering just 9.5 liters per second, proved that water reuse was not only possible, but practical – even in rural communities.

Cities Embrace Desalination

In 2025, Antofagasta became the first major Chilean city to rely entirely on desalinated seawater. The system delivers more than 1,400 liters per second. It now supplies both Antofagasta and nearby Mejillones, proving that desalination can serve large urban populations, not just industry.

Meanwhile, hybrid models are emerging. In Puchuncaví, a desal plant that will supply both municipal and industrial users is being developed, aiming to reduce conflict and share infrastructure costs across sectors.

Policy Catches Up

Chile’s rapid transition was made possible by swift policy reform. Until 2023, the national water code treated treated wastewater as public water, limiting its reuse. That changed with the “Just Water Transition” framework. New regulations gave municipalities and utilities the authority to treat and sell reclaimed water for non-potable use.

The effects were immediate. In May 2025, national utility Econssa awarded a $292 million, 35-year concession to to convert Antofagasta’s wastewater system into a large-scale reuse network. When operational, it will deliver 900 liters per second of reclaimed water for parks, street cleaning, and industrial processes. It will become the largest such facility in Latin America.

Reuse initiatives are also scaling in Santiago and Valparaíso, where reclaimed water will irrigate green belts and support peri-urban agriculture. The national target is to double reuse volumes by 2030.

A Public–Private Transformation

Chile’s progress is the product of effective collaboration. Private organisations working with the chilean governement have been able to expand modular desalination and reported annual water savings of over 16 million cubic meters across northern operations in 2024, while also upgrading Santiago’s three largest wastewater plants into energy-positive “biofactories” — facilities that recover biogas and nutrients, and pave the way for indirect potable reuse.

Local operators are also stepping up. Supported by government grants and international loans, these players are piloting decentralized reuse systems in smaller towns. Funding from institutions such as the Inter-American Development Bank and CAF has helped close infrastructure gaps.

What the World Can Learn

Chile offers lessons that extend far beyond Latin America:

• Start where the pressure is highest. Mining created demand, but agriculture and cities followed quickly.
• Legal frameworks matter. Unlocking reuse required policy change, not just technology.
• Public trust is essential. Pilots that demonstrated visible local benefits built acceptance.
• Integration is key. Reuse and desalination are not competitors — they are complementary.
• Infrastructure must match climate reality. National resilience comes from planning, not reaction.

Looking Ahead

The drought has not ended. Climate pressures remain. Chile’s response is strategy-focused, looking ahead towards providing water security for the next generation. Reuse and desalination are now embedded in national water planning. At the 2025 IRDRA Seville Colloquium, Chile’s story was shared to offer more than inspiration. It served as evidence, that water resilience is not theoretical, but possible. Built not in laboratories, but in the dry valleys of Coquimbo and the coastal cities of the Atacama. We would like to especially thank, José Luis Murillo Collado, CEO at Esval, for his insights during the Colloquium.

Chile, now is a beacon of light for reuse and desalination. Where scarcity once ruled, innovation and perserverance is rewriting the future. ¡Viva Chile lindo!

Chilean miner Antofagasta Minerals inaugurated a more than $2 billion desalination plant in 2024 for its flagship copper mine in Chile, Los Pelambres, aimed at relieving the effects of severe drought that has hit production.

A water reuse plant in Chile

References (APA style)

Cochilco. (2024, June 27). Chile’s copper miners will need more energy, water to keep up production. Reuters. https://www.reuters.com/markets/commodities/chiles-copper-miners-will-need-more-energy-water-keep-up-production-cochilco-2024-06-27/ 

Field, J. (2025, July 17). Mining companies are pumping seawater into the driest place on Earth. The Guardian. https://www.theguardian.com/global-development/2025/jul/17/green-transition-water-chile-atacama-desalination-plants-lithium-copper-mining 

White & Case. (2025, June 9). Perspectives on water: Growing demand for water projects in Latin America. https://www.whitecase.com/insight-alert/perspectives-water-growing-demand-projects-latin-america 

Inter Press Service. (2023). Treated wastewater sustains crops in Chile’s arid north. https://www.ipsnews.net/2023/09/treated-wastewater-sustains-crops-chiles-arid-north/ 

Smart Water Magazine. (2025, March 28). Antofagasta becomes first major Latin American city fully supplied by desalination. https://smartwatermagazine.com/news/smart-water-magazine/antofagasta-1st-major-latin-american-city-fully-supplied-desalination 

Smart Water Magazine. (2025, May 19). Sacyr awarded $292 million water reuse P3 project in Antofagasta, Chile. https://smartwatermagazine.com/news/smart-water-magazine/sacyr-awarded-292-million-water-reuse-p3-project-antofagasta-chile 

OECD. (2024). Environmental performance review: Chile. OECD Publishing. 

Sacyr. (2025, May 8). Sacyr awarded contract for water reuse treatment and distribution P3 project in Antofagasta, Chile. https://sacyr.com/en/-/water-reuse-treatment-plant-antofagasta