Just how much water does Mexico's mining industry consume?

Mexico's President Andrés Manuel López Obrador (AMLO) has repeatedly accused the mining industry of being one of the country's biggest water consumers, and has used this line of attack to justify not granting miners any concessions during his four years in power. 

"That's why we [also] haven't approved fracking, like in other parts – because of the excessive use of water .... And we haven't given out any mining concession since we've been governing because they're abusers," AMLO said in an August press conference.

But data from water regulator Conagua does not back up the president's rhetoric.

Conagua's water rights registry shows that 75% of water extracted under concessions in 2021 was done so by the agricultural sector, followed by public supply (15%) and the electric power industry (4.5%), excluding hydroelectric generation. The remaining 5.2% was distributed among the entire industrial sector, including the mining industry.

Going into more detail, in its 2022 sustainability report, Mexican mining chamber Camimex said mining only accounted for 0.35% of total national water consumption.

“Any other industry consumes more water than us,” Luis Humberto Vázquez, president of Mexico’s mining engineers, metallurgists and geologists association (AIMMGM), told BNamericas.  

"Consumption of water by mines doesn’t even reach 1% of total water, according to data from everyone and from Conagua itself, where they say that almost 80% of water is used by the agricultural industry."

However, he admitted that mining could not be ignored in terms of overconsumption of available water because there is often water stress in the remote areas where mining companies frequently operate.

“You can't consume water if people don't have water. We have to see how we can help them have water and they can help us. I can assure you that the regulations and standards that we have for consumption of water are very strict. We recirculate 100% of the water .... We almost try not to consume freshwater,” he said.

HIGHLY REGULATED

The Camimex report states that the Mexican mining-metallurgical sector complies with five general environmental laws, including the national water law; five technical specifications and parameters established in official Mexican standards, including one for hazardous waste and wastewater discharges; and five other regulations applicable exclusively to the sector, including for tailings dams, leaching of gold, silver and copper, and mine waste management plans.

Mario Hernández, KPMG's lead corporate tax partner in Mexico, told BNamericas that "mining uses large amounts [of water] and it is polluted by the chemicals it uses. The downside is that much of the water it uses cannot be returned for use.”

However, Camimex explains that, for this reason mining companies are taking steps to reduce consumption of first-use water through strict controls and by upping the use of treated wastewater in their operations. Companies affiliated to Camimex now operate some 70 wastewater treatment plants, according to its 2022 report.

Water is essential for the mining-metallurgical industry because it is used to process minerals, for chemical reactions, cooling industrial equipment, control and prevention of emissions (dust suppression), and transportation of tailings, among other things.

Independent mining and environmental consultant, Paloma García, said it was "a myth" that the mining sector is a "big consumer" of water, because, although it is vital for operations, it is a costly input.

"You have to pay per cubic meter and mining is in the north, where there is drought, where water is more expensive and they have chosen to use science and technology – closed circuits with little evaporation and constant reuse of water," the consultant told BNamericas.

In 2021, more than 5Mm3 of water was recirculated by miner Industrias Peñoles through its water efficiency project, while Minera Media Luna reduced consumption of first-use water in its operations by collecting and using rainwater, according to Camimex.

"Water is an issue that is fairly well addressed and it's used very responsibly by the mining sector," added García.

CONCESSIONS

AMLO was asked at a press conference a few months ago, whether Conagua would stop granting concessions to companies in states that are suffering from drought.

"In some cases. For example, mining – everything that involves. That’s why we haven’t authorized fracking, like in other places, due to its excessive use of water ... and we haven’t awarded any mining concessions since we’ve been in government, because they’ve abused it," López Obrador said.

“The problem will never be solved if they’re going to continue granting concessions left and right. You have to think that it’s not just capital that’s important. The labor force is important and water is important in a productive process, like gas, but not merely capital," the president added.

Conagua is responsible for approving concessions or permits to use water for each mining operation, in accordance with the current legal framework. These permits are issued based on the availability of water in the area where a project is located.