Illustration by Global Voices, showing the Río Grande and a backhoe. The background image is from the Facebook page of the municipality San Pedro de Chicozapotes, used with their permission.

The Río Grande, located in the Cuicatec region of Oaxaca, southern Mexico, is one of the many waterways contributing to the more than 50 billion tonnes of sand removed annually, where the absence of adequate monitoring by Mexican authorities has left families as the only witnesses to over a decade of extraction. After water, sand is the most widely used resource globally.

In the town of San Pedro Chicozapotes, a giant amate tree measuring at least 25 metres high has fallen across the river’s 300 metre-wide flow. On one side, where there is only sand and gravel, a backhoe removes this material every day without stopping, filling one dump truck after another. “These machines never stop working. Right now they are hurrying to extract the sand in order to store it for use over the rainy season,” says local environmental defender Don Ismael. “Then, when the rains end,” he adds angrily, “they will return to the river again.”

Ismael is a pseudonym used to protect his identity, given the safety concerns and fear of reprisals in San Pedro Chicozapotes. According to the Mexican Centre for Environmental Law (CEMDA), Oaxaca is the deadliest Mexican state for environmental defenders. Ismael is a 51-year-old man, originally from Chicozapotes, a small community of Cuicatec and Afro-Mexican people located in the north, 3.4 kilometres from the municipality of San Juan Bautista Cuicatlán.

Backhoes extracting sand from the Río Grande in Oaxaca. Photo: Juana García, used with her permission.

Ismael recounts that, as a child, he would go with his friends to swim in different parts of the Río Grande, where they would collect quelites (edible herbs), fish in certain zones of the river, play, and walk on the sand. Since childhood, he explains, the river has been part of his home, just as it is for the families of the dozen communities that share land with the great river.

He recalls being able to swim anywhere in the river without considering the danger it posed; back then, there was no extraction creating risk zones: “We knew where the natural depths were and which parts were safe from the currents, so we got in and out without worry. But now it’s not safe because of the extraction of sand and gravel. The river is also more polluted and deforested; there are areas completely devoid of the trees and plants that we used to see 10 years ago. Before, any place among these trees was nice to lie down in; now you only see piles of stones,” he says, pointing to sections where the backhoe continues digging.

Given its role in the construction of homes and other infrastructure, sand is an essential material for economic development. According to a 2022 report by the United Nations Environment Programme (UNEP), however, “its extraction from places where it plays an active role, such as rivers and coastal and marine ecosystems, leads to erosion, salinization of waterways, the loss of protection from storm surges, and the deterioration of biodiversity.”

The river’s force has gradually changed. Now, locals say that when the river level rises, it carries away everything in its path, washing away the banks, knocking down trees, and destroying the flora, because — as the locals have documented — the areas that previously had sand no longer do.

Lawyer and environmental activist Liudmila Oropeza Fuentes, originally from the Cuicatec region, adds that the area from which the sand is extracted has become private property: “It used to be a public passage where everyone could come and enjoy the river, walk through the whole area towards Cuicatlán, but not anymore; now, it is practically fenced off and guarded.”

Nature is not a pool of resources; it is the source of life

On April 5, 2025, in San Pedro Chicozapotes, community authorities, ejido (a communal form of land management) representatives, community members, and residents held the first Forum for the Defence and Conservation of the Río Grande to reiterate their rejection of the sand and gravel extraction that has been taking place for more than a decade.

During the forum, they took the opportunity to highlight their fight through community organisation, although Oropeza Fuentes recognises that it isn’t easy: those exploiting the river have influence and power, within both the Oaxaca state government and the federal government, as well as within the commercial sector.

At the forum and in other small meetings, various residents and community leaders have begun organising to form a defence front. They have agreed to visit different villages along the river, as well as those in the uplands, to raise awareness about the implications of sand extraction and pollution, and the importance of water and the river.

According to Oropeza Fuentes, Chicozapotes residents “believe that, at any moment, they will not only be impacted by sand extraction, but also by deforestation, drought, and other challenges that are arising.” While they understand that the only way to halt the plunder of natural resources is through community organisation, they are afraid to speak openly about it due to fear of reprisals.

Residents have always opposed the extraction of their resources, but it was only in 2019 that the agricultural authorities decided to report the uncontrolled extraction of sand, stones, and gravel. Ismael maintains that it hurts residents deeply to see the river in its current state: “The plunder doesn’t only pose a threat to our lives, but also to everything that lives in the river: the plants, the animals. Before, you would see fish in many more areas.”

It’s midday and we have walked along the shore for at least a kilometre. In the middle of the Río Grande, Ismael points to the piles of sand and stones in the distance as he describes how the plunder of the waterway has progressed. Along the way, we collect quelites for Ismael’s family; in some stretches, we came across a couple of bulls under the shade of willow trees.

Although there is no one representing the defence, the community’s position is clear. “We will not let them continue to steal our resources,” Oropeza Fuentes declares. “Little by little, we will speak with more residents and communities to give this fight a name.”

Unregulated destruction of the river

Exploitation of the Río Grande is not limited to San Pedro Chicozapotes; it spans across the river’s entirety. Locals recall that the extraction started even before 2010. In those days, anyone could extract the sand for minor construction work, but this wasn’t such a problem because it was excessive. However, in 2015, the Concha Ojeda family began a large-scale business venture.

Although sand extraction is permitted, the quantity that is removed is unregulated. “Sand and gravel are among the most extracted resources by volume, possibly one of the most profitable sectors of illegal trade and, at the same time, one of the least regulated,” states the international bank BBVA in the sustainability section of its 2022 Global Sand Observatory report.

Sand and gravel accumulated from extraction in this now-private zone. Photo: Juana García, used with her permission.

In 2018, the agricultural authorities of the community — residents who manage the land and its use — began to investigate who was responsible for the plundering of the sand and gravel. They approached various government bodies responsible for monitoring natural resources, which led them to Elpidio Desiderio Concha Arellano.

In Chicozapotes, businessman, politician, and former civil servant Concha Arellano has been spotlighted, over the course of several years, for excessively exploiting various zones of the river, during which time the communal landowners say “there has not been an inch of support for the community; it has only been for his own benefit.”

Originally from the municipality of San Juan Cuicatlán in the state of Oaxaca, Concha Arellano was a federal deputy for the Institutional Revolutionary Party (PRI) from 2009 to 2012. He then rose to various positions of responsibility within the party and the government.

His daughter, Lizbeth Anaid Concha Ojeda, is currently a local deputy and president of the Permanent Commission on Government and Agrarian Affairs in the Oaxaca Legislature. This has led to accusations that the family used its influence to speedily manage and validate permits for stone extraction, following pressure from the authorities and residents of Chicozapotes. Concha Arellano is also accused of influence-peddling on behalf of his son, as authorities claim he began exploiting the river without authorisation from the relevant agencies before 2010, prior to his son being granted river exploitation permits, which expire in 2029.

“If you look at this part, it’s just rocks, but further down it’s all green, which is how the whole river should be,” says Ismael, especially because the waterway is part of the Tehuacán-Cuicatlán Biosphere Reserve, a protected natural area in Mexico and a World Heritage Site since 2018.

Otters and endemic species being lost to extraction

The near-threatened Darwiniothamnus tenuifolius in Galápagos. Photo: Will Pollard/iNaturalist (CC BY-NC)

On a sunny spring day with a temperature of almost 40 degrees Celsius, we walk documenting the sand extraction. There are areas where the machinery hasn’t interrupted the fauna or the flora. In these zones, locals confirm that the Darwiniothamnus tenuifolius, known as Darwin's Aster or palo de agua, blooms alongside other species.

According to the Charles Darwin Foundation journal Sew Me in Your Garden, it is a near-threatened species that can only be found on Ecuador’s Galapagos Islands. However, locals in San Pedro Chicozapotes say the palo de agua has always been part of the river, alongside quelites, willows, and other plants. It is now being lost.

Darwiniothamnus tenuifolius, que se supone que se encuentra en el Río Grande, en Oaxaca (México). Foto: Juana García, utilizada con su permiso.

“We used to find palo de agua all along the river, but now — look over there — we no longer do,” reiterates Ismael. “Sand provides habitats and breeding areas for a great diversity of flora and fauna, and it plays a vital role in supporting biodiversity. However, there is still no one documenting these important species.”

Approximately 30 kilometres away from San Pedro Chicozapotes, in the Tehuacán-Cuicatlán Biosphere Reserve, the banks of the Río Grande form the habitat of the neotropical river otter (Lontra longicaudis), one of only three in Mexico. In October 2005, the species’ presence was confirmed through the discovery of 21 droppings and footprints.

Yet, as some areas of the river become deeper, the current becomes more and more forceful. If this continues, the damage could be irreversible, and many species that inhabit the river could suffer greatly as a result.

The near-threatened Central Neotropical River Otter (Lontra longicaudis). Photo: Carlos Sánchez/iNaturalist (CC-BY-NC)

Meanwhile, the Cuicatec inhabitants of Chicozapotes and other communities that coexist with the Río Grande hope that the extraction will stop, although regulation feels far off. The struggle is also becoming increasingly difficult because of social conditions, violence, and the criminalisation of land defenders in Mexico.

According to CEMDA’s annual report, 25 land defenders were assassinated in Mexico in 2024, an increase of 25 percent in comparison to 2023. The report also documented at least 20 incidents of criminalisation that same year — and with 15 attacks, Oaxaca is the state with the highest number. “We have no choice but to keep organising ourselves,” emphasises Ismael, “for the river.”

Environmental Defenders Series

This article series, in collaboration with Latin America Bureau (LAB), documents the work of environmental defenders in different Latin American and Caribbean countries, highlighting both the dangers they face and their achievements in defending their habitats and communities.