Chile expands its desal ambitions while wastewater reuse takes its first steps

Chile wants to expand the presence of desalination plants across the country, including small-scale facilities for rural potable water systems. At the same time, wastewater reuse is taking its first steps through a US$292 million (mn) initiative from state-owned water firm Econssa that began construction on November 10. 

“We are happy when we have a new desalination plant, but we need hundreds of them,” public works subsecretary Danilo Núñez said during a water challenges seminar held by Econssa.

As of October 2025, there are 51 active large-scale desalination active projects in Chile, worth US$24.5 billion (bn) in investments. Meanwhile, 32 plants of the same size are in operation with a combined capacity of 14,227 liters per second (l/s), according to a survey from the country’s desalination and water reuse association Acades and the capital assets corporation (CBC).

Although most of Chile’s desalination drive has been led by the mining sector, there is growing emphasis on multipurpose facilities and those focused on human consumption, such as the US$318mn desalination concession being tendered for Coquimbo region. 

Loreto Araya, head of the water projects division of concessions office DGC, told BNamericas that smaller desalination plants are being studied for drought-stricken areas such as the Petorca and Limarí river valleys, located in Valparaíso and Coquimbo regions, respectively.

The public works ministry (MOP) is also developing small plants for rural services, Araya said at the same event. 

Wastewater Reuse

Econssa’s first large-scale wastewater reuse project, which was awarded to Sacyr Agua, consists of a facility that will treat up to 900l/s of pre-treated water that is currently discharged via a submarine emissary in Antofagasta region’s namesake capital, which will be later be transported via 70km of pipelines to the Salar del Carmen area.

This is expected to benefit the operations of mining companies such as Glencore, Capstone Copper and Codelco.

“There’s an intent from [Econssa’s] board to push all projects that allow the reuse of wastewater along the coastal border,” the firm’s projects and corporate sustainability chief Óscar Vásquez told BNamericas.

Unlike projects involving wastewater discharged into rivers, which often spark disputes over water rights, discharges from submarine emissaries are generally conflict-free.

However, when asked about replicating the Antofagasta project in other regions, Vásquez said such efforts are barely at the study stage.

(The original version of this content was written in English)