MONTERREY, Mexico — Three months pregnant and queasy with morning sickness, Yasmin Acosta Ruiz pushed a cart laden with buckets of water through the scorching July heat. As she and her 7-year-old son eased the cart over a speed bump, water sloshed onto the pavement. They both winced.

Here on the outskirts of Monterrey, a sprawling industrial city that has become the face of Mexico’s water crisis, every drop counts.

Drought has drained the three reservoirs that provide about 60% of the water for the region’s 5 million residents. Most homes now receive water for only a few hours each morning. And on the city’s periphery, many taps have run dry.

Over the last two weeks, water had flowed in Acosta’s home just once, for several hours. The rest of the time — to flush the toilet, launder clothing, wash dishes or bathe — Acosta had to haul water by hand from a well in a park half a mile away. It was not potable, so she had to buy bottled water to cook with.

“It’s like we’ve gone back in time,” she said, wiping sweat from her forehead as she finished her eighth trip to the well that day. “And tomorrow I’ll have to do it all over again.”

The crisis has sparked widespread upheaval, with frustrated residents blocking major highways in protest and people in other parts of the state setting fire to pipes that were supposed to divert emergency flows to the city.

Many are angry at government officials and also the region’s mega-factories, which have largely continued work as usual thanks to federal concessions that allow them to suck water from the strained aquifer via private wells.

Experts say the crisis unfolding here is a stark warning for the rest of Mexico — as well as the American West.

“It should be a wake-up call,” said Samuel Sandoval Solis, an expert in water management at UC Davis who described the situation in Monterrey as a “crystal ball” for Southern California.

Both are densely packed metropolitan centers that rely heavily on faraway water sources.

Monterrey sits at the semiarid tail of the Rio Grande basin, which stretches 1,800 miles from the snowcapped Colorado Rockies to the Gulf of Mexico and is fed by tributaries from both sides of the border. The reservoirs behind two of the three dams that serve it are nearly empty.

Southern California cities, which import about 55% of their water from the Colorado River and Northern California, have already been forced to reduce water usage and face the prospect of further cuts as drought persists and federal pressure mounts on the region to take less from the Colorado.

“Monterrey has the perfect storm of over-drafted aquifers, low reservoirs and water imports that are low,” Sandoval Solis said. “You see the exact same thing in Los Angeles.”

One difference, though, is that Mexico has been slower than California to plan for a future with less water.

Water has never been a given in poor parts of Mexico. Around half of Mexican households with access to piped water receive services on an intermittent basis, according to census data. Even rainy Mexico City faces occasional cuts in service because it lacks sufficient water catchment systems.

Monterrey was supposed to be different. Two hours south of the U.S. border, it is one of the wealthiest cities in Mexico, home to gleaming office towers, luxury car dealerships and modern factories that supply Americans with appliances, vehicles, soft drinks and steel.

The high salaries here relative to other parts of the country have drawn millions of workers, with the city’s population tripling over the last four decades.

Its water management plan has not kept pace.

To supplement the dams, officials planned to build a massive aqueduct that would ferry water from the Rio Panuco, 300 miles south. But the project was canceled in 2016 after the main contractor was implicated in a corruption scandal.

Water experts have been warning for years that the city was on an unsustainable path, that it was, as Sandoval Solis put it, “a ticking time bomb.”

Then drought hit, and their worst fears came true.

Along with the southwestern United States, nearly 60% of Mexico is in drought. Climatologists say it is linked to the weather event known as La Niña, whose effects are intensifying with climate change,

“We’re in an extreme climate crisis,” Nuevo León Gov. Samuel Garcia said recently. “Today we’re all living it and suffering.”

The region’s resources have been strained in other ways.

Under a 1944 treaty, Mexico is required to give the United States a set amount of water from its Rio Grande tributaries. In 2020, that allocation was set to come from Chihuahua state, but after farmers there mounted violent protests, Mexican President Andrés Manuel López Obrador decided to give the Americans water from two international dams on the Texas border. In turn, downstream Mexican farmers who relied on that water were given flows from El Cuchillo Dam, which feeds Monterrey.

Juan Ignacio Barragán, the director of Monterrey’s water agency, says there is no immediate end in sight to the crisis.

The agency is scrambling to close illegal wells and pipeline diversions, which he said proliferate because there are only a handful of federal inspectors monitoring water usage in northern Mexico. It is planning construction of a wastewater recycling plant, is drilling more wells and has another large dam project underway.

The aim is to have enough water for 10 million inhabitants by 2050.

In the meantime, he is asking the region’s businesses to help.

Ternium, a major steel plant here, is giving 40 gallons a second from its well to the city’s water system. The Heineken plant is drilling a well for public use. PepsiCo has donated thousands of gallons of bottled water.

The Topo Chico factory, which is at the foot of a craggy mountain here with the same name, has long allowed local residents to fill up jugs with drinkable water outside the plant. Now people are coming from all over the city, waiting for hours to procure water for bathing and other necessities.

But the fact that the region’s biggest factories have seen no cuts to their water supplies doesn’t sit well with many, including López Obrador. This week the president threatened to shut down beverage factories unless they do more to help.

Margarita Estrada, 71, also thinks the industry should redirect well water to residents.

“Which is more important, beer or the community?” she said, referring to the breweries that proliferate in Monterrey and largely provide for the American market. “The priority should be here.”

She was wilting in 100-degree heat in front of a tanker truck that had come to distribute water to her neighborhood, which hadn’t had running water in three days.

As a worker filled her steel tub with a hose, Estrada and a neighbor commiserated.

“I say God is mad at us,” said the neighbor. “There are clouds in the sky but it never rains.”

“No, we’re to blame,” said Estrada. “We haven’t taken care of the environment.”

Behind them more than 40 people were waiting, some hiding from the sun under umbrellas. They pushed baby carriages, stolen shopping carts and trash cans — anything with wheels to help them lug gallons of water home.

Some men helped Estrada heave the tub into the back of her 1974 Chevrolet truck. Back at her house, she would unload it herself, bucket by bucket.

A single mother who raised seven children and who helped pressure authorities to bring paved roads to this neighborhood, she’s used to hardship. But the daily hunt for water was beginning to take a toll. “We’re suffering,” she said.

There’s no question that the crisis is hitting poor people hardest.

Middle-class and wealthy residents typically have catchment systems that allow them to store the limited water coming from their taps in rooftop tanks.

In San Pedro Garza Garcia, a Monterrey suburb that is the wealthiest area in Mexico, some houses have green lawns and brimming swimming pools.

Barragán, the head of the water agency, said San Pedro has had cuts to its water supply, but less than in other places because it is near a major aqueduct. Neighborhoods farther away suffer more, because the water pressure is so low that it doesn’t always reach them.

Vivienne Bennett, a professor emerita at Cal State San Marcos who wrote a book about a previous water crisis in Monterrey during the 1970s and 1980s, said the industrialists who helped establish the city as a manufacturing powerhouse ensured that factories and wealthy neighborhoods had the best water infrastructure.

A protest movement led by frustrated women resulted in some meaningful changes, including the construction of a new dam and the installation of piped water into the homes of 300,000 people, Bennett said. But Monterrey’s underlying predicament remains: The infrastructure isn’t keeping up with rapid growth.

“It’s been mind-boggling to see the crisis develop again,” she said.

About 20 miles northwest of San Pedro Garza Garcia is a more humble city that is called simply Garcia. Here, densely packed housing developments are filled with workers, many from out of state, who toil at nearby factories churning out Caterpillar tractors, Carrier air conditioners and Mercedes-Benz buses.

It took an hour for a truck carrying more than 4,000 gallons of water to reach Garcia in the heavy evening traffic. When it pulled up on residential block, people came running.

Francisco Saldaña, 27, hurried to fill buckets before he started the night shift at a nearby plant. As soon as he dropped them off at home, his 22-year-old wife started bathing their two young daughters for the first time in days.

As she combed their wet hair on the sidewalk, she chatted with her mother, who lives across the street. Her mother, Nora Diaz, 41, had risen at 3:30 a.m. to see if there would be water when she turned on the faucet. For the third day in a row, there wasn’t. She left about an hour later for her job at an auto parts factory, embarrassed by her greasy hair.

On the factory floor, she and her friends talked about how it was possible that the plant had water to flush toilets and cool down machines when its workers didn’t have enough water at home to prepare beans.

The plants in her beloved garden — herbs, flowers, a peach tree — were drooping a little in the heat. But how could she give them water when she and her family didn’t have enough to drink?

On her $10-a-day salary, she didn’t have money to waste on bottled water. “Sometimes when you’re thirsty, you just suck on your own saliva,” Diaz said.

“I’m mad,” she continued. “But I don’t know who to be mad at.”

Cecilia Sánchez in The Times’ Mexico City bureau contributed to this report.