Northern Mexico has a historic water shortage. These maps explain why.
As demand for water has grown, researchers say a lack of rain has combined with mismanagement to cause one of the worst droughts in the northern half of the country
Ranchers in rural areas have lost livestock or sold their herds prematurely because they can’t feed them.
“People are making lines to obtain a few liters of water. … I wonder how it is possible that they reach this level?” said Víctor Magaña-Rueda, a climatologist at the National Autonomous University of Mexico. “In March, nobody was talking about the socioeconomic drought, and, all of a sudden, we realized that Monterrey was facing one of the worst droughts ever seen in the area.”
For more than a year, northern Mexico has experienced abnormally dry to exceptional drought conditions, but water shortages have become increasingly dire in recent months.
As demand has grown, researchers say a lack of rain and, especially, water mismanagement have led to one of the worst droughts in the northern half of the country. As populations continue to increase and temperatures keep rising, speeding up evaporation from the land surface, water problems will worsen without better adaptation.
“We should really change water management not only in terms of climate change and what may result from it, but also in terms of water demands. Our population has grown. Water demands grow. So things should change,” Magaña-Rueda said.
Dry conditions are not rare in northern Mexico. Much of the land consists of desert or is semiarid, typically receiving less than 30 inches of rain per year.
Rainfall this year has been lower than normal, however. Northeastern Mexico has been persistently dry since January, receiving no rainfall in some months, which is somewhat unusual even during the dry season.
The North American Drought Monitor shows drought conditions across Mexico, a finding that is primarily based on precipitation amounts; about half of the country is experiencing at least a moderate drought.
Drought intensity
Data as of June 30
Abnormally
dry
Exceptional
drought
U.S.
Gulf of
Mexico
Mexico
Mexico City
Drought intensity
Data as of June 30
Abnormally dry
Exceptional drought
U.S.
Gulf of
Mexico
Mexico
Mexico City
Pacific
Ocean
Drought intensity
Data as of June 30
Abnormally dry
Exceptional drought
United States
Sonora
Chihuahua
Coahuila
Gulf of
Mexico
Nuevo
Leon
Mexico
Mexico City
Pacific
Ocean
Belize
Guat.
Oceanographer Benjamín Martínez López said some of the rainfall deficit results from the temporary presence of La Niña, which is characterized by a cooling of surface waters in the equatorial Pacific Ocean. The lower ocean temperatures are linked to fewer clouds, less rainfall and more evaporation in northeastern Mexico.
Increased temperatures associated with human-caused climate change can also intensify evaporation, dry out soils and worsen drought. Mexico has warmed about 2.7 degrees Fahrenheit (1.5 degrees Celsius) since preindustrial times. The Intergovernmental Panel on Climate Change has documented an increase in drought in the region and expects this condition to worsen in the future as temperatures rise.
Human-induced climate change can also amplify the effects of naturally occurring patterns, such as La Niña.
Researchers say, however, that the low rainfall and rising surface temperatures do not fully explain the water shortages, especially in Monterrey.
“Monterrey has been increasing their water consumption very, very rapidly,” Magaña-Rueda said.
Water levels in the three dams that supply water to the city are dwindling. In July, level was so low in the Cerro Prieto reservoir that no water could be extracted. The Presa Rodrigo Gómez reservoir, commonly known as La Boca reservoir, is also nearly empty, as shown in satellite imagery at the top of the page and below. The reservoir near El Cuchillo Dam, which lies east of Monterrey, was at less than half-capacity a few weeks ago.
Detail
MEXICO
2021 shoreline
Dam
Santiago
2022
shoreline
1/4 MILE
Note: 2021 shoreline is the median extent between
June 28 and July 12. 2022 shoreline is the median
extent between June 27 and July 11.
Source: Planet Labs PBC
Detail
MEXICO
2021 shoreline
Dam
Santiago
2022
shoreline
1/4 MILE
Note: 2021 shoreline is the median extent between
June 28 and July 12. 2022 shoreline is the median
extent between June 27 and July 11.
Source: Planet Labs PBC
Detail
MEXICO
2021 shoreline
Dam
Santiago
2022
shoreline
1/4 MILE
Note: 2021 shoreline is the median extent between June 28 and July 12. 2022 shoreline is the median
extent between June 27 and July 11.
Source: Planet Labs PBC
Groundwater is also near record lows. The resource is used to supplement supplies when surface water is unavailable or running low, and it is overexploited during drought. It usually takes months to years to replenish. As of Aug. 1, satellite data showed groundwater across northern Mexico was near record lows, compared with the long-term average.
“What this shows is that they are pumping a lot of water to face the drought,” said Magaña-Rueda, who also cited illegal pumping from wells. “There is no real control … and it’s more critical in regions where precipitation is, in general, meager, like in northern Mexico.”
Groundwater conditions
Groundwater wetness percentile as of
Aug. 1, compared with 1948-2012
Drier
Wetter
U.S.
Gulf of
Mexico
Mexico
Mexico City
Groundwater conditions
Groundwater wetness percentile as of
Aug. 1, compared with 1948-2012
Drier
Wetter
U.S.
Gulf of
Mexico
Mexico
Mexico City
Groundwater conditions
Groundwater wetness percentile as of Aug. 1, compared with 1948-2012
Drier
Wetter
United States
Sonora
Chihuahua
Coahuila
Nuevo Laredo
Gulf of
Mexico
Nuevo
Leon
Monterrey
Mexico
Pacific
Ocean
Mexico City
Belize
Guatemala
Groundwater conditions
Groundwater wetness percentile as of Aug. 1, compared with 1948-2012
Drier
Wetter
Tijuana
United States
Sonora
Hermosillo
Coahuila
Chihuahua
Nuevo Laredo
Nuevo
Leon
Gulf of
Mexico
Monterrey
La Paz
Mexico
Mazatlán
Cancún
Guadalajara
Pacific
Ocean
Mexico City
Veracruz
Belize
Oaxaca
Guatemala
Benjamín Ordoñez-Díaz, an adjunct researcher at the Monterrey Institute of Technology, said water demand has risen in recent decades because of a growing population and an increase in the number of large companies and in agriculture activity. Monterrey’s population has doubled since 1990, with the metropolitan area exceeding 5 million people today.
“The drought in the past only affects cattle and farmers in the beginning, but in this moment affects families, affects farmers, cattle and all the industries who have been developing in this area,” Ordoñez-Díaz said.
Much of the drought has affected people in poorer neighborhoods. While authorities limited residents’ supply of water, several large Monterrey companies, including breweries and soda factories, continued to receive the supply of water needed to maintain their activities.
“People in Monterrey don’t have access to water, but at the same time, you get pictures from golf fields — green — receiving enough water,” said López, the oceanographer, who also is a lecturer at the National Autonomous University of Mexico. “The distribution of water is not okay.”
Mexican President Andrés Manuel López Obrador acknowledged that growing industrial demand has strained water supplies and called on companies and farmers to give some of their water to the public during the drought. Heineken, the beer producer, offered some of its water allocation and donated a well.
When the drought will end is uncertain. Many are relying on tropical cyclones to bring water to the desert and replenish reservoirs. Hurricane forecasters have projected an above-average Atlantic hurricane season, another effect of La Niña, but activity has been low so far in the season, which began June 1. Forecasters expect it to pick up soon, but depending on tropical cyclones for rainfall is risky in a constantly changing climate.
“Expecting a tropical cyclone to help water management in the region is not an intelligent activity,” said Magaña-Rueda. “We have been maintaining the same practices as a few decades ago, and so that is unsustainable.”
Magaña-Rueda said the government and locals need to implement more sustainable practices, including less overall water consumption, even outside of drought. People need to diversify water sources, relying not only on surface and groundwater in a warming world. The government also should create better drought mitigation plans and update water policies, he said.
“The best time to act against drought is when there is no drought,” said Magaña-Rueda. “That is what adaptation is all about.”
About this story
Groundwater conditions data sourced from NASA Grace. Drought monitor data sourced from North American Drought Monitor. Satellite imagery and reservoir shoreline extents for 2021 and 2022 sourced from analysis by Planet Labs PBC.
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