by Andrés Ruzo
The numbers settle, and I finally have my first temperature: 85.6°C, or around 186°F. At this elevation, water boils just under 100°C (212°F)—these waters are not boiling, but it’s close enough to shock me. I definitely didn’t expect this high a reading. Your average cup of coffee is served at around 54°C (130°F). Water becomes painful and dangerous around 47°C (around 117°F). Dipping my hand into the river would give me third-degree burns in less than half a second. Falling in could easily kill me.
After years of questions, doubts, literature reviews, dead ends, and frustrations, here at last is the Boiling River. The accounts may still be exaggerated, but clearly not by much.
I let the thermometer cool and repeat the measurement a few times. The temperatures consistently plot around 86°C (around 187°F). The temperatures, though impressive, are typical of many volcanic and nonvolcanic geothermal systems. It’s the scale—the sheer volume of flowing water—that seems unbelievable. You need a powerful heat source to produce this much hot water. I’d expect to see something of this scale in the Yellowstone supervolcano or in Iceland’s volcanic rift zone, but not in the middle of the Amazon, more than four hundred miles from the nearest active volcano. Where does all this water come from? Where does it get its heat? How can this river exist?
Geochemical water sampling at the Boiling River. This site, far upriver, is called the Mermaid’s Waterfall. It is said to be home to a mermaid spirit.
I mark the location on my GPS. As expected, we’re in the Agua Caliente Dome. I look south, worry crinkling my brow. About a mile and a half away is Peru’s oldest Amazonian oilfield. I sure hope this place is natural. Just then, my aunt emerges from the cliff top near the Came Renaco. “I told you it was real!” she calls over the churning river.
Descending the stone steps, Guida makes her way to where I’m sitting, surrounded by my instruments. She relays that Maestro left for Pucallpa this morning with a big group of foreign patients and most of the Mayantuyacu community. She reassures me that we will meet him at the Pucallpa office tomorrow on our way back to the airport, but I worry. Now that I’ve seen the river, I need to understand it—and that means taking samples I can analyze back in the lab. Natural feature or not, the river is sacred to this community, and taking samples of their sacred waters without Maestro’s permission is out of the question.
“So,” she says, “what do you think?”
“It’s amazing. I see it—but it’s so incredible, I’m struggling to truly comprehend it.” I pause. Then I blurt out, “I just really hope it’s natural.” I hadn’t meant to voice my concern and immediately regret it.
Guida is surprised. “What do you mean?” she asks.
As a scientist, I tell her, when I’m confronted with something I don’t understand, I try to come up with possible explanations—hypotheses. I can think of three that would account for the river. The waters could be heated by magma deep underground, like at Yellowstone— but this is unlikely here, as no study has ever identified any magma bodies in the area. The second explanation is that the waters are being heated by the earth itself. Even without local magma bodies, the earth’s crust gets hotter the deeper down you go; we call this the geothermal gradient. If the waters are being heated by the geothermal gradient, then they are likely coming from deep in the earth. But waters cool as they flow up to the surface, so to have this much high-temperature water requires impressively fast flow rates from the bowels of the earth to the surface. Regardless of the cause, if it is natural, it is one of the largest geothermal features—volcanic or nonvolcanic—I’ve ever seen.
I hesitate, then explain the third hypothesis: that the river is not a natural phenomenon at all, that we’re a mile and a half north of the oldest oilfield in the Peruvian Amazon. The river could be the result of an oilfield accident—an abandoned oil well producing hot water, or oilfield waters reinjected into the earth that are heating up and flowing out to the surface again. That’s why I urgently need to find the 1933 Moran study, which might describe the river before human development began.
“Wow,” Guida says softly. “So how do you find the answer?”
“First I need to ask Maestro’s permission to study the river,” I say. “It will take years to really understand this place, but step one is done—I know the river’s exact location, and that its high temperatures aren’t exaggerated.” Guida casts me a smug smile.
“Once we’re back in Lima, I’ll review the studies of this area—fortunately, we’re in a well-studied region. Then I’ll try to contact the local oil company for information about their activities in this area.
“I want to come back for a longer stay next year, with a research team. I’m going to need help measuring the river’s temperatures along its entire flow path to identify the river’s pattern of heating.”
“Pattern of heating?”
“Does it heat up at a single point or at multiple points over a larger area? If, hypothetically, the hot waters come from an old oil well, then there should be a single, major heating point where the old well is buried or hidden.
“For now, I’d like to take water samples. Waters have chemical ‘fingerprints,’ which can be analyzed in a lab to shed light on things like whether they come from a known geothermal aquifer, or have magmatic or oilfield signatures. But I need permission first.”
Steep cliffs bound parts of the Boiling River. Together with thick jungle, this terrain can make field work a challenge. The environment demands that every step be intentional and well calculated; falling into the river below would have serious consequences.
“What will you do if you find that it’s an oilfield accident?” Guida asks uneasily.
“No idea—become very unpopular with the locals, I guess?” We laugh, but the idea turns my stomach. “Seriously, though,” I say, “I’d do the right thing and report it.”
“Then become very unpopular with the locals,” Guida says. “And if it’s natural?”
“Then I’ll have proof that the world is more amazing than I could have ever imagined.”
8
The Shaman
The half-moon wraps the jungle in its soft light, and the river roars its lullaby as a curtain of vapor rises from its waters. Hungry insects prowl outside my bed’s mosquito net. Darkness conceals the world’s distractions, leaving me alone with my thoughts.
I miss Sofía and struggle excitedly with how to tell her about today. I could fill volumes with the day’s stories, experiences, and descriptions—but even then I’d have to summarize the journey’s precious details. No story, no scientific study, no picture or video could ever do this place justice. Maybe that’s why they say it’s sacred.
Earlier today, Brunswick led us about a mile upriver, deep into the jungle. Every plant we passed had medicinal value, and each feature along the river was home to a different spirit. We saw large pools, one with a powerful waterfall about twenty feet tall—all with dangerously hot water.
Brunswick gave me permission to collect water samples, on the condition that I double-check with Maestro when we get to Pucallpa. He watched with interest as I carefully filled each bottle with scalding water and recorded every detail about each location.
Though I measured water temperatures up to 91°C (around 196°F), I discovered that the river begins as a cold stream. Along its path, it’s supercharged at three major thermal injection zones. This heating pattern gives me hope that the river may be natural after all—if the water was flowing from an abandoned oil well, it would only be heated at a single point. But there is still the possibility of reinjected oilfield waters heating up and flowing to the surface through natural fault zones. I need more data before I can prove anything.
Far upstream, just before the first thermal injection zone, a great sandstone boulder resembling a serpent’s head emerges from the jungle. Brunswick identified it as the most sacred site on the river, home to the Yacumama, or “Mother of the Waters”—a giant serpent spirit who births hot and cold waters. Beneath the
great serpent rock’s “jaws,” a hot spring mixes with the cold stream water, bringing the legend to life.
Brunswick said the river has existed since before the time of the grandfathers, and that it represents both life and death. Death is everywhere here—early on our walk I saw an unfortunate frog fall into the river and boil alive. The river decorates itself with the bones of those who don’t keep a respectful distance.
But in spite of the scalding waters, life abounds. Vegetation erupts from every patch of soil, and no matter where we looked something was crawling, calling, or slithering. I was taken aback to see algae growing in the river despite the near-boiling waters.
While I took water samples, Brunswick told me about the patients who come here to heal. Admittance is exclusively by word of mouth—the only way to be allowed in is if a “friend of Mayantuyacu” advocates for you, as Guida had done for me. Despite this, almost all the patients are foreign, chiefly Europeans and North Americans. Brunswick also said that anthropologists and psychologists come to study Mayantuyacu’s traditional healing methods and natural medicines. This must be the best-known unknown site in the world, I think, not for the first time.
A victim of the river. The Boiling River here is around 80°C (176°F), and falling in at these temperatures means near-instant third-degree burns, muscles cooking on the bone, and no easy way out.
But no one has ever come to study the river, Brunswick tells me. In the past people attributed the heat to the Yacumama spirit. Now, locals and foreigners just assume that the heat is from a volcano.
In the morning, the sun pierces the windows and holes in my wooden hut. I awaken to the harmonious sounds of the jungle. I meticulously pack my instruments and precious water samples for the long trip back to Lima.
Heading over to the kitchen hut, I see Brunswick and ask him where I can get some tea. He hands me a mug and a tea bag, then points down to the river. I laugh—but he indicates his own steaming mug. He is serious! Walking down to the river, I consider all the heavy metals and other nasty things, organic and inorganic, that are often found in geothermal waters. Still, when in Rome . . .
I dip my mug into the river and pull it out. Eddies of steam rise from the mug to caress my face as I peer in to see the clear, odorless water. Once it cools, I take my first sip. The water has a clean and pleasant taste. I drink my tea by the river, saying a private farewell before we retrace yesterday’s journey and head back to the city.
Back in Pucallpa, Guida and I find ourselves standing before a familiar green door. I feel a surge of nervous excitement knowing Maestro Juan is just on the other side of this door. What will he have to say to me?
Guida knocks and soon the door swings open. A stout Amazonian woman stands before us.
“Sandra!” Guida exclaims. The old friends embrace, and Guida introduces me.
“We’ve heard a lot about you,” Sandra says, taking me in. “It’s not every day you meet someone interested in volcanoes and hot rivers. It’s a bit odd. I’m just glad you didn’t fall in!” Placing her hand on my arm, she says, “We know Guida would only bring us good people. Come in, please!” She leads us into the decorated office where our journey started yesterday.
A man gets up from his seat. He appears to be in his sixties. He wears a Nike T-shirt, long brown shorts, long socks, and no shoes.
Though we are far from Mayantuyacu, I feel the jungle’s presence in the room. His skin is the chocolate hue of the Pachitea, and his short hair and piercing eyes are as black as the forest night.
Maestro Juan gives me a reserved handshake. We take our seats. Guida and Sandra catch up while I sit in uncomfortable silence. Maestro remains as still as a stone, but he is clearly taking in every detail, and I can tell I’m being studied.
“Andrés, what did you think of Mayantuyacu?” Sandra asks me. I feel Maestro’s serpentine gaze focus on me.
“Amazing,” I manage. “The river is an absolute wonder—of Peru and of the world.”
“A wonder?” Maestro breaks his silence, looking me in the eye. “And what makes a wonder?” he asks in a low, earthy voice, sitting forward in his seat.
“That’s a good question,” I say nervously. Then gesturing to the images on the walls, I say, “Look—the ‘Wonders of Peru.’ They are all special places. I’ve been lucky enough to see many of them, but Marcahuasi is the one I know best—I first went up when I was twelve.”
His gaze narrows. “That is a far place to go for a twelve-year-old.”
“It’s important to my family,” I reply.
“Dr. Daniel Ruzo.”
“Yes! How did you know?”
“I once went up to Marcahuasi for a few days to study—to learn from the dead,” he says solemnly. “Dr. Daniel Ruzo is very respected by the people of Marcahuasi.”
“He was my great-grandfather,” I say. “He died when I was very young, so I never really got to know him. But he loved Marcahuasi, and I feel connected to him there.”
Maestro’s gaze softens. “It is important to connect with the ancestors.”
I nod in agreement. “I felt very connected to him recently when his widow gave me some of his old things.” I pause, smiling at the memory. “Something funny happened that day. When she learned I had become a geologist, she laughed and said, ‘There is no single group of people whom your great-grandfather detested more than geologists!’ Then she looked up to heaven and said, ‘See, Daniel? Karma!’ ”
“Why karma?” Maestro asks.
“Well, my great-grandfather had his own ideas about what carved the monoliths of Marcahuasi. Geologists disagreed with him, and it didn’t bring out the best in him—to put it nicely.”
A toothy grin spreads across Maestro’s face. “So who do you honor—your great-grandfather, or his friends?”
“I don’t think it’s about honoring either group,” I reply. “It’s about honoring Marcahuasi. Nature tells its own story. Sometimes we misread it—but there is a difference between being open to any outcome and only looking for the one you want. I say this respectfully, but my great-grandfather was not a scientist, and in his writings he seems more interested in proving his point than listening to nature.”
Maestro smiles. “The plants teach us to heal people. We must listen to them to make the medicines. You can hurt people if you don’t listen properly.” He pauses again. “Why do you study geology?”
“Well, I love being outside,” I say with a smile. “But really, I feel that geology gives me the best chance to save the world, as I use it to try to find better ways to produce energy and resources.
“I’m blessed to call three countries my own: Peru, Nicaragua, and the United States. They’re very different places, but they have similar needs, such as clean air and water, economic stability, a healthy society—all of which are tied, either directly or indirectly, to how we use our natural resources. So if we find better ways to produce and use our energy and resources we simultaneously work to solve these other issues. In the end, I think that if we take care of nature, she will take care of us. And geology is my way of honoring her.”
For a long time—uncomfortably long—Maestro does not respond. Finally a smile snakes across his face and he bursts into a laugh.
“I understand now,” he says tenderly. “I am a curandero (healer) of humanity—my mission is to heal people. You are a curandero of the earth—your mission is to heal it. Nature belongs to all countries, and is not confined by borders—and neither are you, my young doctor. You were made for this mission, and so were born a twin soul to nature herself. It is important for you to do your studies, and you have my blessing to study at Mayantuyacu.”
I am speechless.
“Good surprise, no?” Maestro laughs again.
I thank him profusely and express my hope to return soon. “Maestro, one more thing—” I say.
“Yes?”
I pull out a plastic grocery bag containing the water samples. “I collected these samples yesterday. I wanted to ask your perm
ission first, but because you weren’t there I consulted with Brunswick, who said to bring them to you and ask if I could take them.”
“You already have your permission,” he says softly, pulling out a bottle and contemplating it. “Thank you for showing me these. You’re a good kid.” Then, standing up, he says, “I have something for you.” He disappears into an adjacent room and reemerges with something in his hand. He drops it into mine. It’s cold with smooth undulations. “It’s an encanto from the jungle—a talisman for protection on your mission.”
A fossilized oyster. It fits perfectly in the palm of my hand. “Thank you,” I say, admiring the smooth texture of the gray shell.
“There is one more thing I want to ask of you,” Maestro says. Again he picks up one of the water samples. “After you study the waters, pour them out onto the ground, wherever you are in the world, so the waters can find their way back home.”
9
A Long-Awaited Return
Night falls on Mayantuyacu, and the jungle teems with life. Bats emerge from their roosts, maneuvering through the darkness with their otherworldly pitches. Frogs and insects belt out their songs. Spiders’ eyes shine like dew as they move through the jungle. Looming over it all, vividly present even in the dark, is the river—bellowing out its roar, filling the cool night air with billowing clouds.
The revving of an electric generator interrupts the nighttime chorus and overwhelms the organic noises. The lightbulbs flicker on in the maloca—the large, traditional Amazonian longhouse at the center of the Mayantuyacu community.
It’s July 2012, and I’m back in the jungle after eight months in Dallas. Organizing this fieldwork season was an uphill battle. My doctoral committee was concerned that the Boiling River was becoming a distraction. “You’re so far along in your geothermal mapping work”—one committee member told me—“putting it on hold to study this river, which will likely take years of study to do it right, seems like a bad idea.”
