Alejandro Gómez has been without adequate running water for more than three months. Sometimes it lasts an hour or two, but only a small trickle, barely enough to fill a couple of buckets. Then he swims for many days.

Gómez, who lives in the Tlalpan district of Mexico City, does not have a large storage tank, so he cannot get tanker deliveries; There’s just nowhere to store it. Instead, he and his family barely get what they can buy and store.

When washed, they capture runoff water to flush the toilet. It’s difficult, he told CNN. “We need water, it is essential for everything.”

Water shortages are not uncommon in this neighborhood, but this time it feels different, Gomez said. “Right now we are having this hot weather. It’s even worse, things are more complicated.”

Mexico City, a sprawling metropolis of nearly 22 million people and one of the largest cities in the world, faces a serious water crisis as a tangle of problems – including geography, chaotic urban development and infrastructure leaking – are exacerbated by the impacts of climate change.

Years of abnormally low rainfall, longer dry spells and high temperatures have added stress to a water system already struggling to cope with increased demand. Authorities have been forced to impose significant restrictions on water pumped from reservoirs.

“Several neighborhoods have been suffering from a lack of water for weeks and there are still four months before the rains begin,” said Christian Domínguez Sarmiento, an atmospheric scientist at the National Autonomous University of Mexico (UNAM).

Politicians are downplaying any sense of crisis, but some experts say the situation has reached such critical levels that Mexico City could be approaching “day zero” in a matter of months, when taps run dry in large swathes of the city.

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All-time lows

Densely populated Mexico City sprawls across a high-altitude lake bed, about 7,300 feet above sea level. It was built on clay-rich soil (which it is now sinking into) and is prone to earthquakes and highly vulnerable to climate change. It may be one of the last places anyone would choose to build a megacity today.

The Aztecs chose this place to build their city of Tenochtitlán in 1325, when it was a series of lakes. They built on an island, expanding the city outward, building networks of canals and bridges to work with the water.

But when the Spanish arrived in the early 16th century, they tore down much of the city, drained the lake bed, filled in canals, and destroyed forests. They saw “water as an enemy to overcome for the city to prosper,” said José Alfredo Ramírez, an architect and co-director of Groundlab, a design and policy research organization.

An aerial view of Mexico City, one of the largest megacities in the world.  - César Rodríguez/Bloomberg/Getty Images

An aerial view of Mexico City, one of the largest megacities in the world. – César Rodríguez/Bloomberg/Getty Images

His decision paved the way for many of Mexico City’s modern problems. Wetlands and rivers have been replaced by concrete and asphalt. In the rainy season it floods. In the dry season, it is parched.

About 60% of Mexico City’s water comes from its underground aquifer, but so much has been extracted that the city is sinking at an alarming rate: about 20 inches per year, according to recent research. And the aquifer is not being replenished fast enough. Rainwater slides off the city’s hard, impermeable surfaces, rather than sinking into the ground.

The rest of the city’s water is pumped great distances uphill from sources outside the city, in an incredibly inefficient process, during which around 40% of the water is lost through leaks.

The Cutzamala water system, a network of reservoirs, pumping stations, canals and tunnels, supplies about 25% of the water used by the Valley of Mexico, which includes Mexico City. But a severe drought has taken its toll. Currently at around 39% capacity, it has been languishing at a record low.

“It’s almost half the amount of water we should have,” said Fabiola Sosa-Rodríguez, director of economic growth and environment at the Metropolitan Autonomous University of Mexico City.

In October, Conagua, the country’s national water commission, announced that it would restrict Cutzamala’s water by 8% “to ensure the supply of drinking water to the population given the severe drought.”

Just weeks later, officials significantly tightened restrictions, reducing the water supplied by the system by almost 25%, blaming extreme weather conditions.

“Measures will have to be taken to be able to distribute the water that Cutzamala has over time, so that it does not run out,” said Germán Arturo Martínez Santoyo, general director of Conagua, in a statement at the time.

The exposed banks of the Villa Victoria Dam, part of the Cutzamala system, in Villa Victoria, Mexico, on January 26, 2024. - Raquel Cunha/Reuters

The exposed banks of the Villa Victoria Dam, part of the Cutzamala System, in Villa Victoria, Mexico, on January 26, 2024. – Raquel Cunha/Reuters

About 60% of Mexico is experiencing moderate to exceptional drought, according to a February report. Almost 90% of Mexico City is suffering from a severe drought, and it is expected to worsen with the start of the rainy season still months away.

“We are in the middle of the dry season and sustained temperature increases are expected until April or May,” said June Garcia-Becerra, assistant professor of engineering at the University of Northern British Columbia.

Natural climate variability strongly affects this part of Mexico. Three years of La Niña brought drought to the region, and then the arrival of El Niño last year helped cause a painfully short rainy season that failed to replenish reservoirs.

But the long-term trend of human-caused global warming hums in the background, causing longer droughts and fiercer heat waves, as well as heavier rains when they arrive.

“Climate change has made droughts increasingly severe due to lack of water,” said Sarmiento of UNAM. In addition to this, the high temperatures “have caused the water that is available in the Cutzamala system to evaporate,” he stated.

Last summer saw brutal heat waves that hit much of the country, claiming at least 200 lives. These heat waves would have been “virtually impossible” without climate change, according to an analysis by scientists.

Climate impacts have collided with the growing pains of a rapidly expanding city. As the population grows, experts say the centralized water system has not kept pace.

‘Day zero?’

The crisis has sparked fierce debate over whether the city will reach “day zero,” in which the Cutzamala system will fall to such low levels that it will be unable to supply water to city residents.

Local media widely reported in early February that an official at a Conagua affiliate said that without significant rain, “day zero” could arrive as early as June 26.

But authorities have since tried to assure residents that there will be no day zero. in a Press conference On February 14, Mexican President Andrés Manuel López Obrador said work was underway to address water issues. The mayor of Mexico City, Martí Batres Guadarrama, said in a recent Press conference that the day zero reports were “fake news” spread by political opponents.

Conagua declined interview requests from CNN and did not answer specific questions about the prospect of day zero.

But many experts warn of a spiraling crisis. Mexico City could run out of water before the rainy season arrives if it continues to use it the same way, Sosa-Rodríguez said. “We are likely facing day zero,” she added.

A woman washes dishes at home after receiving a free distribution of water in the Iztapalapa neighborhood on January 31, 2024. - Henry Romero/Reuters

A woman washes dishes at home after receiving a free distribution of water in the Iztapalapa neighborhood on January 31, 2024. – Henry Romero/Reuters

This does not mean a total collapse of the water system, he said, because the city does not depend on a single source. It won’t be the same as when Cape Town in South Africa came dangerously close to being completely dry in 2018 after a severe multi-year drought. “Some groups will still have water,” she said, “but most people won’t.”

Raúl Rodríguez Márquez, president of the nonprofit Water Advisory Council, said he doesn’t think the city will reach day zero this year, but warned it will if changes aren’t made.

“We are in a critical situation and we could reach an extreme situation in the coming months,” he told CNN.

“I don’t think anyone is prepared”

For almost a decade, Sosa-Rodríguez said he has been warning officials about the danger of a day zero for Mexico City.

He said the solutions are clear: Better wastewater treatment would increase water availability and decrease pollution, while rainwater harvesting systems could capture and treat rain and allow residents to reduce their dependence on water. water network or tanker trucks by 30%.

Fixing the leaks would make the system much more efficient and reduce the volume of water that must be extracted from the aquifer. And nature-based solutions, such as restoring rivers and wetlands, would help provide and purify water, he said, with the added bonus of greening and cooling the city.

In a statement on its website, Conagua said it is carrying out a three-year project to install, develop and improve water infrastructure to help the city address declines in the Cutzamala system, including the addition of new wells and the start-up of water treatment plants.

But in the meantime, tensions are rising as some residents are forced to cope with shortages while others, often in wealthier enclaves, are largely unaffected.

“There is clear inequality in access to water in the city and this is related to people’s income,” Sosa-Rodríguez said. While day zero may not have arrived yet for all of Mexico City, some neighborhoods have been dealing with it for years, she added.

Amanda Martínez, another resident of the city’s Tlalpan district, said water shortages are nothing new for people here. She and her family often have to pay more than $100 for a tank of water from one of the city’s tankers. But it’s getting worse. Sometimes they can go more than two weeks without water and she fears what may come, she told CNN.

“I don’t think anyone is prepared.”

CNN’s Laura Paddison and Jack Guy reported from London, and Fidel Gutiérrez reported from Mexico City.

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By Sam