• Climate change and territorial encroachment drive the remote Matsigenka tribe's fight for clean water in the Amazon, where its absence has long proved deadly
• 'We lived with illness for so long. Many died. It wasn’t easy. We had to fight for clean water,' says village elder Ismael Vicente Shamoko
• 'A lot of these illnesses they conceived of as spiritual probably came from drinking contaminated water,' explains ethnobotanist and medical anthropologist Glenn Shepard

YOMYBATO, Peru 

As Mateo Vicente walks along a forest path to his grandfather’s house, the tranquility of birdsong and trilling insects is ruptured by the drone of a twin-prop plane flying low overhead.

Tracing its path above the canopy, Vicente suspects the aircraft is piloted by drug traffickers.

“They constantly fly over us. If the drug trade comes here, we’ll have no security in our forest,” says the 32-year-old leader of Yomybato, an Indigenous Matsigenka village in Peru’s remote southern Amazon.

Vast forest buffers his village, but Vicente knows the jungle’s expanse will not keep at bay a proliferating trade of coca — the raw ingredient for cocaine that is just one of many threats looming at the edge of his home and snaking its way throughout the Amazon.

Even in the most remote regions, tribes like the Matsigenka are not immune to a changing Amazon, where illegal logging, mining, and other extractive industries are accelerating climate-change-driven fires, drought, and resource insecurity for millions.

In the face of these threats, Yomybato’s over 400 villagers have confronted a quieter but no less formidable challenge: securing safe drinking water in a region defined by rivers and rainfall.

Arriving at his grandfather Ismael Vicente Shamoko’s thatched-roof home, the two drink cool, clean water from a tap steps from his patio — a simple act belying a monumental feat in the Amazon.

Here, an untreated gulp could prove fatal if it is laced with deadly contaminants. It is a striking paradox: though 20% of Earth’s freshwater originates in the Amazon, millions of its residents lack access to clean sources.

“We lived with illness for so long. Many died. It wasn’t easy. We had to fight for clean water,” said Shamoko, who lost his brother and several other family members to waterborne illness.

Shamoko founded Yomybato in the 1980s. It was not until 2012, years after nearly losing his own children to diarrhea, that he partnered Yomybato with water-focused non-profit Rainforest Flow. Together, they built a low-tech, adaptable filtration system that today delivers clean water to nearly every dwelling.

The work was tireless. The Matsigenka first had to source a natural underground reservoir and lay a 7.5-kilometer (4.7-mile) water line through dense jungle, where it is captured and filtered with sand and rock.

As climate pressures strain the Amazon’s ecosystems, experts warn that food and water insecurity could deepen with global repercussions. Natural water filtration systems like Yomybato’s could serve as a blueprint for millions to ease water scarcity and prevent chronic disease in the Amazon.  

Jungle refuge at risk

Far from Peru’s sprawling coastal capital, Lima, the Matsigenka live inside Manu National Park, a 1.5 million-hectare (3.7 million-acre) shrine of mega-biodiversity where the Andes yield to the lowland forests of the Amazon.

A UNESCO World Heritage Site, the park spans a landmass the size of the US state of Connecticut, yet is home to just 1,200 Indigenous people.

It is a protected biosphere, spared the wholesale invasion suffered by other Amazon regions. Here, isolated tribes still live as hunter-gatherers, and groups of Matsigenka, including those in Yomybato, live in villages with limited interaction with outsiders.

In the 1950s, American missionaries contacted and settled dispersed Matsigenka families, drawing them out of isolation and gathering them into larger, permanent communities inside what would become Manu National Park.

Following epidemics and the brutalities of the 19th- and 20th-century rubber trade, some Matsigenka fled to distant headwaters where they remain today, living in semi-isolation.

Recently, Matsigenka living along those remote ravines have established stronger ties with their settled kin in Yomybato. Seeking medicine and tools, many of these so-called “uncontacted” Matsigenka suffer from waterborne illnesses and are increasingly drawn to Yomybato for access to clean water.

“Little by little, families are coming to live here. They come with nothing but their children and the tunics on their backs. We’ve invited them to stay,” said Vicente.

Peru is home to the second-largest population of isolated tribes on Earth after Brazil. Some 7,500 people from roughly 25 ethnicities live in isolation or are in the early stages of contact with wider society.

The peaceful integration of over a dozen isolated Matsigenka families into village life stands in contrast with other isolated tribes reeling from an influx of outsiders.

Last August, loggers operating along the rim of the Manu National Park were killed by the isolated Mashco Piro tribe, a group that has rejected contact with the outside world for generations.

Such violent encounters in the Amazon’s most inaccessible areas are the result of both legal and illegal actors pushing deeper into the forest for its resources.

Despite the Matsigenka’s relative insulation within the national park, illegal loggers and miners flank the surrounding buffer zone, making Indigenous groups increasingly vulnerable.

In 2024, deforestation stripped 141,781 hectares (over 350,348 acres) of primary forest from Peru’s Amazon, according to the Monitoring of the Andean Amazon Project. Human-caused fires for agriculture destroyed another 47,574 hectares.

Beyond invasion lies another existential threat: drought and rising temperatures caused by climate change are drying up rivers and streams crucial to the survival of Indigenous populations.

If forest loss continues unchecked, scientists project that by 2050, up to 47% of Amazonian forests could suffer ecosystem shifts that will accelerate climate change.  

Turning the tide on waterborne illness

As vital water sources dry up, communities are exposed to an increased risk of waterborne disease.

In Yomybato, before villagers gained access to clean water, rates of parasitic infection, anemia, and childhood mortality from drinking pathogen-ridden water soared.

“Traditionally, (the Matsigenka) understood this as plant and animal spirits taking vengeance on children for slights and disobedience,” explained Glenn Shepard, an ethnobotanist and medical anthropologist who has worked with the Matsigenka for decades. “A lot of these illnesses they conceived of as spiritual probably came from drinking contaminated water,” he said.

That changed when Rainforest Flow partnered with the Matsigenka, giving them the tools to build and sustain clean water systems.

Built to adapt to remote environments, Rainforest Flow’s systems are relatively simple, gravity-fed, and rely on natural filtration. They have had a profound health impact on the residents of remote villages, often neglected by state authorities.

In Yomybato and neighboring Tayakome, the Matsigenka laid the pipes, hauled sand, and established Water Committees — Indigenous teams that build, maintain, and regularly test their water with portable labs. The results have been a 74% reduction in deaths from diarrhea, a steep drop in anemia and malnourishment, and improved sanitation.

For Yomybato native and water committee member Alejo Machipango, the fight to bring clean water to his community was marked by tragedy. He joined the committee after the death of two of his children from dysentery, aiming to ensure clean water in his village and to train others.

“I saw the contaminated water samples with my own eyes and understood these illnesses weren’t coming from the air or spirits — they were coming from the water,” said Machipango.

Scaling the model, Rainforest Flow’s founder and director, Nancy Santullo, alongside the Matsigenka, has replicated the project in four other communities representing several ethnic groups.

“When they first turned on that tap, lifetimes of encroachment began washing away,” she said. “The project is about coming together in times of need, pooling resources and wisdom, and creating something that benefits the long-term health and well-being of the people.”