It is the scale of the Boiling River that is truly impressive. It flows hot for just less than four miles, can get up to 80 feet wide at its widest point, and up to 15 feet deep in others. The thermal flow is a result of fault-fed hot springs super-charging the river with geothermal waters bubbling up from below; Photograph by Devlin Gandy

A Legendary Boiling River Flows Through the Amazon. Can It Be Saved?

ByKelley McMillan

February 18, 2016

7 min read

The Boiling River is at the center of life of Mayantuyacu—essential as a source of water, cooking, cleaning, making medicines, even telling time. At the Boiling River, you regularly hear locals refer to “la hora del vapor” (“the vapor hour”). It refers to the end of the day before nightfall, when cooler air temperatures create great plumes of vapor rising up from the river. “La hora del vapor” is a time of relaxation, meditation, and even enjoying the natural sauna; Photograph by Devlin Gandy

As a kid growing up in Peru, Nicaragua, and Texas, Andrés Ruzo heard a legend about a boiling river deep in the heart of the Amazon. Years later in 2011, Ruzo, by then a geoscientist working on a thermal map of Peru, traveled by car, canoe, and foot to a remote swath of the Amazon populated by white-throated toucans, jaguars, and indigenous tribes with a rich shamanic culture to see if the myth was true.

There amid the dense central Peruvian Amazon, over 400 miles from the nearest volcano, he came upon the Boiling River, a flowing, four-mile-long river as wide as a two-lane road, 16 feet deep in places, and averaging 186ºF—hot enough to cook a small animal in seconds.

Though the local people had long known about the river, it had never been studied by scientists, which meant that in this age of information saturation, Ruzo had stumbled upon a scientific discovery of the highest order: what’s thought to be one of the largest thermal rivers on the planet, made even more unusual by the fact that it’s not heated by volcanic activity.

Since his discovery of the Boiling River, which was aided by National Geographic grants, Ruzo has devoted his life to studying and preserving it, as well as the jungle surrounding it. This week, he debuted his book The Boiling River: Adventure and Discovery in the Amazon, as well as the Boiling River Project, a nonprofit dedicated to protecting the river; the adjacent jungle, which is threatened by loggers, farmers, and oil companies; and the indigenous people who live there.

Here, he discusses the significance of the Boiling River, why we must act now to protect it, and discovery in the age of information.

What is the Boiling River Project?

The Boiling River Project is a U.S.-based nonprofit that has the ultimate goal of protecting the Boiling River of the Amazon, a site that’s in a jungle considered open for development and disappearing rapidly. We’re doing this through scientific research, as well as educational initiatives. Ultimately, it’s about saving the site and declaring it a Peruvian national monument.

Downriver from Mayantuyacu, lies the second Amazonian shamanic community—Santuario Huistín. Both communities have been integral in supporting the scientific work done at the Boiling River. The locals have been curious about the research and excitement to gain a better understanding of their sacred river. Here, Andrés shows a Huistín community member how to use a thermal camera; Photograph by Devlin Gandy

Why is this site so significant?

There are multiple ways of defining its significance. The first one is the cultural aspect. The Boiling River is really the focal point of traditional knowledge in the central Peruvian Amazon. According to one of the local shamans, this is an ancient center of shamanic learning.

Then you’ve got this great geological significance. It’s an anomalously large geothermal feature, which basically means it’s freaking big. The large thermal rivers that I’ve come across are overwhelmingly next to volcanoes, and the thing about this one is that we’re over 700 kilometers [435 miles] away from the nearest active volcanic center, in the middle of a sedimentary basin.

To understand the processes and mechanisms that result in the Boiling River, Andrés has been conducting geochemical studies, with yearly field sampling, for five years. He studies the water’s isotopic composition, as well as elements present in the samples in order to characterize the waters and understand how they are interacting with the local geology. Here, Andrés is taking water samples at the Smoking Walls— where steaming, fault-fed thermal springs along the Boiling River veil the cliff-face in vapor; Photograph by Devlin Gandy

What’s heating the river?

It’s fault-fed, which means that the water sinks down deep, spends some time underground taking heat from the earth, and then shoots back up through faults and cracks in the Earth’s surface to create this anomalously large thermal river.

What are the biggest threats to the Boiling River?

The biggest one is deforestation and that’s directly a result of it being in this jungle that’s considered open to development, jungle that’s considered exploitable legally.

Why must action be taken now?

The clearest example is this: In 2011, when I first went to the Boiling River, from Pucallpa, the largest city in the central Peruvian Amazon, it was two hours by car, followed by 30 to 45 minutes in a motorized canoe, followed by an hour or more of hiking to get to the Boiling River site. As of 2014, the way that I arrived to the jungle was a direct, three-hour drive from Pucallpa. No more canoe, no more walking—that’s how fast deforestation is advancing.

What are the next steps for the project?

With this new grant from National Geographic, number one, we’ll try and close the geologic study chapter. Number two, we’re opening up the outreach component, the conservation effort to the public, which you can see on http://www.boilingriver.org.

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What’s your ultimate goal for this project?

It’s for sure protecting the site. The first stage is getting the legal structure in place to declare it a Peruvian national monument and to ensure that the surrounding jungle is no longer considered open for any type of development. If we could limit that to eco-touristic development, non-clear-cutting development, that would be a big thing.

What are your thoughts on discovery in this age of information?

The true discoveries, the never before seen things, I think those are still out there. Then I think you have these discoveries that are about rethinking something we thought we had known about, and I think discovery for the future is going to be about that. So you’ve got discovery of existence versus discovery of significance.

Why have you devoted so much of your life to this project?

A biblical verse comes to mind. There’s a parable about a person who finds a treasure in a field and sells all that he has to buy that field and find that treasure. For me, this place is just so special. It’s redefined what it means to be sacred.

For more information on the Boiling River, visit: www.boilingriver.org.