First Episode TEST – DELETE

In August 2018, a small team gathered at Tony Grove in northern Utah to push the terminal sump of Main Drain Cave.

Main Drain is the deepest cave in Utah. The entrance sits above 9,000 feet in an alpine glacier basin, and the passage runs 1,227 vertical feet down from there through a chain of technical drops, including a pit called Kilo. At the bottom is water. Beyond the water, in theory, is more cave — dye tracing had already proven the stream reappears at a spring miles down Logan Canyon and thousands of feet lower in elevation. Somewhere between here and there is a lot of undiscovered cave.

Getting a diver to that water is the hard part. Jean puts the logistics at 90% of the total effort: roughly twenty cavers hauling scuba tanks down a series of vertical drops, day after day, on a schedule that asks people to descend a 1,227-foot alpine cave on a Monday, a Wednesday, and a Friday. As Jean puts it, the tanks are “kind of bombs. You don’t want to drop them.”

By the time she and dive partner David Moore reached the sump on day one of the 2018 push, the trip had already started going wrong. Floods the previous year had broken the dive line and pushed the loose pieces into what divers call entanglement hazards. Clearing and repairing it burned two-thirds of their gas instead of the one-third they’d planned.

Then something genuinely strange: the second sump was gone. The flood had blown out whatever was damming it, and where they’d previously had to dive, they simply walked. Beyond it lay virgin passage — a narrowing bedrock canyon with a stream running down it, ending at a waterfall and a third sump nobody had ever seen.

They dove it anyway. It looked like chocolate milk. They found no way on.

The accident happened afterward, back at the main sump, around midnight, with the last protein bar already eaten. Jean’s dry suit zipper snagged. David got a grip, pulled hard, bloodied his knuckles across her chest, and forced it past the bad tooth — and the entire metal zipper fell open behind it. Unfixable.

Between Jean and the surface: five hundred feet of flooded passage at eighty to ninety feet deep, in water her dive computer read at 38 degrees, with no functioning exposure suit.

The alternative was waiting alone, without food, a sleeping bag, or a stove, for a minimum of four days and more realistically six, while David exited the cave and drove to Salt Lake City for gear. She didn’t think she’d survive it.

So they made a plan: strip everything non-essential — including David’s caving helmet — and treat Jean not as a diver but as a load. She would swim for herself as long as she could. When she couldn’t, he would carry her.

What follows on the recording is one of the more remarkable pieces of first-person description I’ve had on a microphone. Jean loses dexterity in her fingers first, then her wrists, then her elbows. Her flooded suit turns her negatively buoyant, so she stops swimming and starts crawling along the bottom, dragging tanks, throwing her arms and legs “around like they were golf clubs” using only her shoulders and hips.

“It’s really weird,” she says. “Just like what it must be like to be paralyzed. And I guess I was just paralyzed.”

She made it. She shook uncontrollably for twenty minutes on the far shore while David stripped her out of the wet gear and got warm water into her.

Then, the next day, he dove the sump again. Alone. To retrieve the tanks — because some of them belonged to other people.

What This Episode Is Really About

Three things stuck with me after this conversation, and none of them are about caves.

Slow disasters are harder than fast ones. Jean makes the point that most accidents arrive without warning — a fall, a rockfall, a kayak flipping. This one gave her an hour to stand in the dark and fully comprehend her situation. She and David talked through sixteen scenarios. Plan A through plan K. That’s not panic. That’s the opposite of panic, and it’s a much rarer skill.

Sunk cost will kill you, and knowing that doesn’t make you immune. Jean names it out loud when they’re staring into the chocolate milk: they’d hauled gear for days, and every hour of that effort was quietly arguing for a dive they’d otherwise skip. She dove it anyway — and was still able to say, out loud, in the moment, that sunk cost was in the room. Naming your own bias while it’s operating on you is about as good as any of us get.

Turnarounds are where people die. She and I both circle this one. In caving it’s called “outhead” — the pull toward the exit that makes you drop your guard, take the shortcut, stop double-checking. The mountaineering literature says the same thing about descents. The objective is not the summit. The objective is the parking lot.

Terms Used in This Episode

• Sump — a section of cave passage completely filled with water, requiring a dive to pass.
• Sump diver vs. cave diver — cave divers generally work in clear water like Florida or the Yucatán. Sump divers work in whatever they get, which is often nothing.
• Diving by braille — navigating a flooded passage in zero visibility, entirely by feel on the dive line.
• Line trap — a dive line pulled into a notch or crack that turns out to be impassable when you come back through it.
• Silt-out — total loss of visibility from disturbed sediment. The floor does it. So does the ceiling, when your bubbles knock the percolation loose.
• Troglobite — an organism adapted to live its entire life underground.
• Outhead — the mental state of just wanting out of the cave. A well-documented way to get hurt.
• Mammalian dive reflex — your body shunting blood from the extremities to protect the core. Why Jean’s hands felt like they were being slammed in a car door.

A Note on Depth

You’ll find Main Drain’s depth listed several different ways online, and most of those numbers are wrong.

The sump sits 1,227 feet below the entrance. I know because I surveyed and mapped this cave. The figure that gets repeated most often on the internet — 1,127 feet — doesn’t match the survey.

If you came here looking for the real number, that’s it.