Advancing Chile’s mining sector through sustainable water solutions

Located in the country’s Atacama Desert, Chile’s Antofagasta region is considered one of the world’s premier copper-producing hubs, but it faces a pressing challenge: freshwater scarcity.

This shortage affects both local communities and the continued growth of the mining industry.  

As Antofagasta Minerals, a Chilean copper mining group, looked to expand its Centinela mining district, the need for a sustainable water solution that would preserve essential continental water resources without the need for desalination¹ became paramount. 

To address the challenge, Almar Water Solutions, a global water infrastructure developer, and Transelec, a leading provider of high-voltage systems in Chile, formed the Aguas Esperanza consortium. Together, they agreed to a $US1.5 billion critical water transportation system to support the expansion of Centinela.  

This partnership included the acquisition and operation of an existing 144-kilometre seawater pipeline and the construction of a second pipeline of equal length, enabling the extraction of an additional 144,000 tonnes of copper, 3,500 tonnes of molybdenum, and 130,000 ounces of gold annually.¹ 

At the heart of the project is an innovative approach: transporting more than 1,100 litres of seawater per second from the Pacific coast to the mine site.¹ By using seawater instead of scarce inland supplies, the project safeguards local aquifers and sets a new standard for environmentally responsible mining. It also advances Antofagasta’s commitment to source 90 per cent of its mining division’s water from seawater, recycled or reused sources by 2025,² helping secure the region’s future and promote sustainable growth.   

Macquarie Capital brought its deep expertise as an infrastructure adviser and investor to the project, serving as exclusive financial adviser and sole private placement agent to Aguas Esperanza.

Collaborating closely with the consortium, Macquarie Capital developed a funding strategy to serve the project’s 17-year concession and operational requirements.

The financing package included a $US510 million, 17-year private placement and a $US593 million, 12-year term loan arranged by a syndicate of leading global banks, alongside an $US81 million letter-of-credit facility.² 

The team also supported the rating process, helping the project achieve investment-grade debt status and secure green loan and green bond certifications. In a market where shorter maturities had become the norm, Macquarie Capital’s financing balanced risk between banks and institutional investors, ensuring both affordability and long-term stability for project sponsors.