Carlos Morales has lived all of his 54 years in San Antonio, a tiny hamlet at the foot of the Andes in Argentina’s western province of Mendoza. In that time he has seen wrenching environmental and demographic change.

“When I was a child my mother had 550 goats,” says Morales, whose family—like the 15 others still living in the community—has Huarpe indigenous roots. “Today, nobody here has more than 50. Sheep were raised here, too, but now there are none because there is hardly any water or grass. That’s why people leave. Only the elderly are staying.”

Morales is one of an estimated 3,000 “laguneros,” Huarpe whose traditions, customs and livelihoods are rooted in the Guanacache Lagoons of Mendoza and the neighboring province of San Juan. The lagoons, now dried out, formed part of a 5,800-square-kilometer (2,239-sq.-mile) network of seasonal wetlands that are now largely parched, too.

Once a haven for waterbirds and other wildlife thanks to water flow from the Mendoza and San Juan Rivers, the area was declared a wetland of international importance in 1999 under the Ramsar Convention in hopes its ecosystem could be restored. The Ramsar site, expanded in 2007 to include additional wetland areas, now encompasses 10,000 square kilometers (3,861 sq. miles).

Experts point to a trend of diminishing water flows that began in the 1950s and worsened dramatically in recent decades due to dam construction, drought and upstream water draws by agricultural operations—Mendoza’s world-famous wine vineyards prominent among them.

Today, one can hike dozens of kilometers in the Guanacache region, where marshes, streams and lagoons once brimmed with water and Huarpe laguneros fished from traditional totora-reed canoes. On a recent morning, Morales guided a visitor through one such area of the former lagoons near San Antonio, now an expanse of dry sand, virtually bare of vegetation save a scattering of small trees and shrubs.

San Antonio and the 11 other villages of the Guanacache Lagoons region, though widely dispersed, have historically shared Huarpe traditions. Among these was the crafting of the totora-reed canoes, which resemble those of the Andean peoples of Bolivia and Peru who live on the shores of Lake Titicaca. Now only the oldest laguneros possess this skill, which due to the dearth of water has lost its practical use. “My father would go out to fish in the lagoons,” says Olga González, 53, a mother of nine children. “But everything has dried out here.”

González and other residents say the main cause is upstream water impoundment and overuse. Says González: “Those responsible for our situation are those who have stolen our water.”

She also blames diminishing rainfall, observing that in recent years, precipitation in a typical 12-month period has occurred only on a few summer days and not at all in the winter. Indeed, experts say that over the past decade, altered weather patterns likely associated with climate change have contributed a great deal. They point to a marked drying trend in the northern and central Andes of both Argentina and Chile.

But they, too, cite overuse of water by upstream agricultural producers and population centers in Mendoza and San Juan.

Mendoza’s wine industry in particular has grown enormously in recent decades, establishing a strong foothold in foreign markets. It has also spurred booming wine tourism that in the first quarter of 2022 helped its main airport attract the third greatest number of international visitors to Argentina behind the top two airports serving Buenos Aires, the national government says.

The thriving vineyards, however, belie the fact that Mendoza is an extremely dry province, receiving barely 200 millimeters (7.9 inches) of precipitation annually. Were it not for the extensive use of irrigation, agricultural activity in the province would likely be limited to certain forms of ranching.

But Mendoza and neighboring San Juan make heavy use of irrigation by tapping the Mendoza and San Juan Rivers, which used to feed the lagoons dependably each summer with water from the melting Andean snowpack.

Mendoza’s agricultural operations occupy so-called ‘oasis’ areas that collectively account for 4.8% of the province’s land and 90% of its 1.8 million people. All are upstream of the Guanacache Lagoons, where there is no irrigation and rainfall averages 120 millimeters (4.7 inches) annually, significantly lower than the province-wide average.

And because water is impounded upstream—in part to povide municipal drinking water but mainly to enable agriculture—the Mendoza and San Juan Rivers now peter out before reaching the Guanacache Lagoons. Marcelo Giraud, a geographer with the National University of Cuyo, says water diversion has been occurring since agricultural activity began expanding in Mendoza and San Juan toward the end of the 19th century.

“The General Water Law of Mendoza, which is still in effect, was drafted in 1884 and was considered advanced in its time because it allowed landowners to seek rights to water for consumption and production,” Giraud says. “That’s why the Guanacache Lagoons only received water that remained after irrigation [and drinking water] needs of Mendoza and San Juan were accommodated.”

But he adds that due to the current drought conditions dating back to 2010: “Even that doesn’t occur…Now there’s nothing left over.”

A major blow to the Guanacache region’s water supply came in 1980, when the Ullúm Dam was completed on the San Juan River, creating a 3,200-hectare (12-square-mile) reservoir that can hold 440 billion liters of water (357,000 acre-feet).

What many residents of the region describe as a final, fatal blow was delivered 20 years later with the construction of the Potrerillos Dam on the Mendoza River. Inaugurated in December 2001, the Potrerillos Dam contains a 900-hectare (3.5-square-mile) far deeper reservoir with a capacity of 450 billion liters (365,000 acre-feet).

The dam provides water for irrigation, drinking and electric power generation in the province’s principal ‘oasis’—the area in and around the city of Mendoza, the provincial capital, which lies roughly 70 kilometers (44 miles) from the Guanacache Lagoons. Its reservoir, which sits 1,380 meters (4,528 feet) above sea level, was designed to store snowmelt descending from the Andes and release it when those flows have tailed off, typically from August to November.

Since 2010, however, prolonged drought in the region has meant less snow on both the Argentine and Chilean sides of the Andes, and less precipitation on Mendoza province’s plains. “Due to the effects of climate change we have a marked decline in precipitation,” says Aníbal Manzur, a geologist who is director of environmental management in the Mendoza province Department of Irrigation. “In 10 of the last 12 years, it snowed only 40% to 60% of the level of normal years. We are in a prolonged dry cycle that is unprecedented in the province’s history, and that is accompanied by an increase in temperatures.”

Adds Manzur: “Water distribution in Mendoza dates from the 20th century, when the prevailing view was that it should be used for human consumption and agricultural and industrial production, and little heed was paid to ecosystems like the Guanacache Lagoons. Today, rural communities are making valid demands for water, but satisfying them involves complex political decisions…[I]t is difficult now to take water away from a social sector that has acquired rights to it.”

In response, Guanacache residents are taking what action they can, an approach that is evident in the circular, partially buried cisterns that are cropping up in the region’s small towns. The 15,000-liter (4,227-gallon), hermetically sealed cisterns are assembled by local teams using square concrete plates and are filled from water trucks or from accompanying wells.

Installation of tanks began in 2016 with help from the Union of Landless, Peasant and Rural Workers (UST), a nonprofit representing low-income rural residents of Mendoza. The group trained local teams to assemble and install the cisterns after learning how to do so from members of a small-farmers’ organization in Córdoba, Argentina, who themselves had acquired the know-how on a trip to rural Brazil.

The aim is to engage local residents in providing a practical, affordable means of water storage for individual families and communal groups, says Juan Burba, an agricultural engineer and UST organizer who has helped oversee the project. “We call this a farmer-to-farmer implementation model,” he says. “We have found solutions ourselves, with local residents themselves learning how to assemble the cisterns.”

Keeping funds local

Burba points out that assembly and installation of the cisterns provides an additional source of income for the men and women who serve on the work crews. As it is, many local residents must leave home for two or three months a year to work on vineyards in irrigated “oasis” communities, since raising livestock in the Guanacache region has become steadily more difficult amid drought and dwindling water supplies.

The teams that install the cisterns are paid out of grant funds UST has obtained from national programs and institutions. So far 40 cisterns have been installed in the Guanacache villages, says Mariana Díaz, a UST member who works as a technical representative in the region for the Argentine Family Agriculture Secretariat. In July five teams of five people each were set to begin construction of 42 more, Díaz says, adding that the program is by no means a panacea.

“These projects do not solve the underlying problem because the water stored in the cisterns does not allow people to have the life they had before, but they have improved the resilience of communities in the region,” she says.

Well installation conducted in conjunction with cistern projects is also financed with UST-administered grant funds and, like the cisterns, reflect a methodology that the Córdoba farmers’ group learned in Brazil and passed on to Guanacache communities. The methodology involves installing concrete rings from top to bottom as the well is dug to safeguard work crews.

But with groundwater supplies diminishing, too, well projects are becoming more challenging. “Before, water could be found at depths of two meters, but today one has to go 10 or 12 meters down, and the water often has a bitter taste and can’t be used for drinking,” says Florencia Morales, 31, a resident of San Antonio.

The municipality of Lavalle, which includes San Antonio and a number of other Guanacache villages, has attempted to address this problem by periodically trucking in water to fill cisterns with the aim of providing rural families 1,000 liters (264 gallons) a month.

Restoring soils

Guanacache Lagoons communities also have worked with institutional and corporate partners to restore the ability of former pastureland to retain water and sustain grass for goat herds. In one such project conducted during 2011-21, for instance, the Argentine affiliate of the international conservation group Wetlands International carried out restoration of 1,000 hectares (2,471 acres) of Guanacache land.

The project was carried out with funding Fundación AVINA, a Latin American philanthropy, and Coca Cola. It involved soil restoration at 23 sites eroded not only by drying of the land, but also by deforestation and overgrazing. Heber Sosa, a biologist and field coordinator for Wetlands International in Mendoza, says work crews built embankments to capture sediment and increase soil depth, and installed membranes to reduce runoff of the summer rainwater needed to promote growth of pasture grasses.

Still, he and other experts recognize that projects such as this one have limited potential to rejuvenate the Guanacache Lagoons ecoysystem if rainfall levels remain low and so much Andean snowmelt is consumed by upstream agricultural, industrial and municipal users.

“The Guanacache Lagoons communities desperately need water,” Sosa says. “Unlike in the case of other environmental problems, we are not talking about risks facing future generations but, rather, what is happening today. Mendoza is the province where wine production shines, but little thought is given to the communities like those of the Huarpe people that lie outside the oases and are suffering a genocide. The laguneros have been converted into men and women of the desert.”