An essay by Sam Johnston, a lead guide and instructor at Montana River Guides and an instructor and spill responder with WRI. Adapted and expanded from his original piece “Into the Marañón: A Self-Supported Kayak Expedition Through the Headwaters of the Amazon,” first published in Downriver Journal, March 2026. Republished with permission.
I was halfway through lunch on a boulder in the Inner Gorge of the Marañón when I almost killed my friend.
We were deep inside one of the most committing sections of whitewater in South America — a place where the canyon walls close in, the rapids stack on top of each other, and the nearest road or clinic is a hundred miles away. We had just finished portaging the upper drops of Wasson’s Slide, picking our way across unstable granite under blistering Peruvian heat. I climbed up a cluster of boulders to scout the next stretch and put my right hand on a rock about the size of a washing machine.
It moved.
I lunged, yelled “Rock!” and watched a several-hundred-pound boulder break loose and surge downhill — directly toward Dayton, who was standing in ankle-deep water below. At the last possible moment, it wedged between two smaller rocks and stopped, inches in front of him. I’ll never forget the look he gave me. Disbelief, then something harder.
I’ve been guiding and paddling rivers for years — I’m a lead guide and instructor at Montana River Guides, and I work alongside the WRI team as an instructor and in spill response. I know better than to put weight on unverified rock in exposed terrain. And in a single unthinking moment, all of that training almost didn’t matter.
That’s the thing about rivers. They expose you. Not in some mystical, poetic way — in a very literal, physical way. They find the gap between what you know and what you actually do when you’re tired and scared, and the temperature is 100 degrees, and you’ve been sick for three days. Expedition kayaking on the Marañón reminded me of five things I thought I already knew about swiftwater safety. I’m writing them down here because every one of them applies just as much to a training exercise on the Clark Fork as it does to a canyon in Peru.
1. Scene size-up is never finished.
We scouted Wasson’s Slide carefully. We identified the main hazards, picked a portage line, and talked through the sequence. What we didn’t scout was the boulder field we were going to sit on to eat lunch. It never occurred to any of us that the lunch spot was part of the hazard.
In a rescue context, this is the lesson that people learn the hard way and then teach for the rest of their careers: the scene doesn’t end at the rapid. It includes the bank you’re standing on, the rock you’re using as an anchor, the eddy your swimmer is drifting toward, and the driftwood pile upstream that could release at any moment. Most of the near-misses I’ve seen on rivers — my own and other people’s — happened during the “safe” parts of the day.
2. Decision-making degrades faster than you think.
Three of our five teammates got violently ill near the end of the Upper Canyon. We sheltered under a bridge in a small town in Ancash while Dayton, Charlie, and Caleb tried to keep fluids down. Jack and I hiked into the village to find supplies — we came back with sporades, canned tuna, and a handful of unlabeled antibiotics from locals who, by the end of the afternoon, were no longer particularly friendly.
Sitting on the hike back, we tried to think through our options. Could we get out from here? What if someone didn’t recover? Would the pills help, or hurt?
None of our answers were good. And the real lesson wasn’t which decision we made — it was how much harder every decision becomes when you’re dehydrated, underslept, under pressure, and your teammates are suffering. In a training environment, I can think clearly. In a real incident, the version of me making the call is a significantly slower version than the one who studied for the test. The systems and checklists we teach in technical rescue courses exist precisely because your brain is the first thing the river takes away from you.
3. Containment is a plan, not a prayer.
Before the trip, I told myself I had a containment plan for the Inner Gorge. What I actually had was a hope — a hope that I wouldn’t swim in the worst part of the canyon, and that if I did, one of my stronger paddlers would be in position to help. A few hundred yards below the Wasson’s portage, I mistimed a stroke and flipped in a hole I shouldn’t have flipped in. I rolled up. But in the seconds underwater, scraping my back across rocks, I understood the difference between a plan and a wish.
A real plan answers the questions: Who is watching me right now? Where do they go if I swim? Where do I go if I come out of the boat? What’s downstream of the next feature, and how many seconds do I have before it matters? In a good swiftwater course, you drill these until they feel tedious. On the Marañón, I was grateful for every repetition — and painfully aware of the ones I had skimped on.
4. Ego is a current you can’t paddle against.
Later in the trip, I stood on shore at Samosera Rapid staring at the biggest whitewater I had ever considered running. A line revealed itself if you looked long enough: start center, drive hard right, thread between two holes, pick up the downstream V. I ran it, and it was the best moment of the expedition.
But before I ran it, I asked myself a question I had been avoiding for the entire trip. Why am I running this? Am I running it because I’ve scouted it and I believe I can make the line? Or am I running it because I’m the least accomplished boater on this team, and I don’t want to be the one who walks?
Those are completely different answers, and they lead to completely different outcomes. One of them gets you through the rapid. The other one gets you fished out of a hole downstream. Every rescue instructor I’ve ever trained with has said some version of the same thing: the most dangerous piece of equipment on the river is the one between your ears, and ego is how it fails. Naming the motivation out loud — even just to yourself — is half the fight.
5. The river is not the enemy.
There’s a story we tell ourselves in hard whitewater: that we’re conquering something, pushing limits, winning. The Marañón cured me of that story pretty quickly. You don’t conquer a river that’s been carving a canyon for millions of years. You visit it for a few days, and if you’re lucky, it lets you leave.
That reframe matters in a rescue context too. The goal of swiftwater/flood rescue training isn’t to dominate the water — it’s to understand it well enough to work with it, to read it, to get your team in and out without anyone getting hurt. The best rescuers I’ve ever seen on a river move like they respect what they’re standing in. The worst ones move like they’re trying to prove something.
Bringing it Home
I came back from the Marañón grateful, exhausted, and covered head to toe in bug bites — and with a renewed appreciation for the training I spend my working life teaching. Not just the technical skills, but the mental framework: scene size-up, decision-making under pressure, containment, honest risk assessment, humility in front of moving water.
Those are the things WRI drills into every student who comes through its facility on the Clark Fork River. I’ve seen them matter on the river, I’ve seen them matter on spill response callouts where I’ve been in the water alongside the WRI team and agency partners, and I saw them matter 8,000 feet down in a canyon in Peru where the nearest help was a hundred miles away. The material is the same. The stakes just change.
If there’s one thing I tell every class I teach, it’s this: the only thing more dangerous than never taking a rescue course is taking one once and assuming you still remember it a decade later. Skills decay. Decision-making decays faster. The best rescuers I know are the ones who keep showing up to refresh, who stay humble about what they’ve forgotten, and who treat every training day like the one where they might actually need it.
WRI’s courses are taught on live water at its facility on the Clark Fork River in Alberton, Montana — swiftwater and flood rescue, rope rescue, ice rescue, boat operations, and fastwater spill response. Whitewater Rescue Institute’s swiftwater, ice, and rope courses are built to NFPA 1006 and 2500 standards; their spill response and boat operations trainings meet the standards for USCG, HAZWOPER, and more. WRI is a USCG-classified Oil Spill Removal Organization. If you’ve been meaning to sign up — or meaning to send your team — this is the year.
See our current course schedule.
I’ll see you out there.
Sam Johnston is a lead guide and instructor at Montana River Guides and works alongside WRI as an instructor and spill responder throughout the region. The original account of his Marañón expedition is available at Downriver Journal.
