(MEXICO CITY) — Mexico City is one of the largest cities in the world, yet it is running out of water. It’s a slow-motion disaster decades in the making, caused by a litany of issues including human-induced climate change.

Residents are deeply concerned about the impending water crisis.

In Mexico City, many treat every drop of water with the utmost care because there is no running water, and rain hasn’t come amid drought. Water is purchased at a great cost for low-income families.

Bernardo Nonato Corona, a resident of the hills surrounding Mexico City, told ABC News he spends 25% of his income on water. And his story is repeated millions of times in Mexico City’s sprawling metropolis.

“Water is very necessary and is used for everything,” Corona said. “To drink it, for the maintenance of the house, for personal use, even for the plants themselves, since it doesn’t rain and you have to water them because it uses up a lot.”

Over the past months and possibly even years, Mexico City’s watershed has been experiencing a notable decrease in rainfall. The effects of this situation are now becoming increasingly visible, ABC News has found. For the first time, many people are openly questioning whether the city will face a water shortage soon.

A majority of Mexico City’s water supply — 60% to 70% — is sourced from aquifers and geological formations of rock and/or sediment that store groundwater, according to Mexico city’s water authority. A recent study found that as much as 5 million Olympic-sized pools of groundwater have been pumped out yearly for the past decade.

The city now relies on rain to fill a reservoir, and groundwater levels are dwindling. However, the ongoing historic drought, exacerbated by human-caused climate change, means a long rainy season is no longer guaranteed, experts told ABC News.

Enrique Lomnitz, founder of Isla Urbana, moved back to Mexico City after attending college in the United States to help his native country overcome its water crisis. He and his organization have been working to save Mexico City from completely losing water.

“So the reservoirs are basically empty,” Lomnitz said. “That’s 30, 40% of the city’s water that we’re no longer getting or we’re getting like a, like a trickle where we used to have a stream. So we’re not recharging our aquifers. We’re pumping an enormous, crazy amount of water out of the ground, because there’s 22 million people over here. And that is the basis of the problem.”

Decades of underinvestment in Mexico City’s water grid mean that about 40% of all water pumped through its pipes is lost due to leaks — the water simply seeps into the ground. When it rains, the city pumps out billions of gallons of water to avoid flooding — water that could theoretically be recycled.

Mexico City’s water system representatives did not respond to ABC News for comment.

On the political front, Mexico’s president-elect and former mayor of Mexico City, Claudia Sheinbaum, held an event on the esplanade of the Coyoacán mayor’s office in Mexico City on May 5, 2024, where she stated, “No scientist, because there is still no science that can do that, could predict this circumstance,” in referencing the current water crisis.

But scientists say droughts are inevitable and planning in advance is possible.

At the same event Sheinbaum said, “We already know where the water is going to come from, how to invest, it is going to be the great investment that we are going to make in the metropolitan area of ​​the Valley of Mexico.”

ABC News reached out to the Sheinbaum campaign to ask what the layout looks like. They did not reply to a request for comment.

As climate change continues, heat waves become more extreme, and droughts grow longer. Everything is at stake for people like Corona and millions more in Mexico City.

“We don’t think about our children, that if tomorrow, the way we are going, water will be more expensive and there will be more water shortages, Corona said. “So if we don’t give a solution to the water issue, I don’t know what will happen tomorrow with our children, our grandchildren.”

The city will have to use its water much more efficiently and sustainably to better prepare for future droughts. Due to a historic drought made worse by climate change, record heat and faulty infrastructure, Mexico City needs to improve its overall water usage.

“I think it’s an existential crisis for the city, but I think that people are incredibly adaptive,” Lomnitz said. “I think people are very resilient. I think Mexico City’s resilient. Mexico City’s been through a whole lot of things. It’s not over.”

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