Record Abyss: Interview with Extreme Diver Krzysztof Starnawski, “I felt I was meant for it”

10 minutes down, 10 hours up. One man, in a submerged cave.

September 27, 2016. 404 meters. The deepest dived underwater cave on the planet.

Meet Krzysztof Starnawski.

It took the Polish extreme diver a lifetime, 20 years to be exact, to finally hit bottom at the legendary Abyss of Hranice.

The cave, located in the Czech Republic an hour’s drive from the Polish border had been teasing Starnawski and his team of volunteers for decades. Until this year when, with the aid of a robot, the storied abyss finally gave up her secrets: a tangle of fallen trees, branches and rubble.

The world record dive was a fact.

Philosopher Friedrich Nietzsche once wrote that when you look into the darkness of the abyss the abyss looks into you. We checked in with Krzysztof Starnawski to find out what Hranice Abyss meant to him and what it took to dive it.

Today, part 1: The technology of extreme cave diving and an interesting comparison between the sport and high altitude mountaineering.

Explorersweb/Pythom: Hi there, Krzysztof. Your expedition proved The Abyss of Hranice is the deepest underwater cave on the planet. You had spent 20 years exploring it, how did it feel to finally reach “the bottom”?

Krzysztof Starnawski: To be exact, we did not reach the bottom of the cave!

I scuba dived 200 meters to a narrowing between two large chambers of the cave and installed a line to guide the Remote Operated Vehicle (ROV) along it.

I ascended to the surface and navigated the ROV operator from there. The machine was fitted with cameras and when it reached 404 meters depth, we could see a steep corridor cluttered with tree stumps and loose rocks.

The corridor headed down. There was a risk the ROV would tangle around rocks and stumps, so we decided to ascend the device.

We proved that Hranička Abyss is deeper than 404 meters, but its accurate depth has not been measured yet. Cameras showed that it certainly goes about 30 m further down, but I have a feeling this cave might be even deeper, judging from the geological characteristics of the area.

The September 27th ROV descent was supposed to be only training but suddenly all started working so well that we finally decided to set it to bed record.

I was overwhelmed with joy, not comparable to anything I have ever felt before. I was very relieved to have closure on this part of my life.

Explorersweb/Pythom: 20 years in a cave is a long time, what made the challenge so formidable?

Krzysztof Starnawski: I scuba dived Hranička Abyss in 1997 for the first time, using open circuit (OC) for breathing.

I submerged to 181 meters in the next few years but the OC gear had its limits: the deeper I went, the more gas cylinders were used and I had to switch them one by one. Operating the OC was so involving that I couldn’t focus on exploration.

It took twelve years to successfully shift to the closed circuit and re-engineer it into a dual CCR system.

I was finally ready to dive really deep and extend the dive time. The only substantial limit left was my own physical endurance to HPNS (high pressure neurological syndrome) and decompression disease.

My body and mind both seemed quite resistant to these disorders, but I still had to train for the challenge.

I did other expeditions and adventures in those 20 years but Hranička Abyss remained my focus. I kept coming back because, for several reasons, I believed that Hranička might turn out to be deeper than the Italian cave Pozzo del Merro, then considered the deepest submerged (392 m) cave in the world.

Hitting 181 meters in 2000 made me realize I was ready to organize and perform extremely difficult dives. I also began to have a feeling that I was meant to do it.

I discovered the passage leading through the narrowing into the deepest parts of the cave during a dive in 2013. It convinced me nothing could stop me now, if only I tried hard enough and would think out of the box.

I have been moving deeper for twenty years, one step at a time. It makes you resistant to doubt and discouragement.

Explorersweb/Pythom: What got you into extreme cave diving in the first place?

Krzysztof Starnawski: I began to climb mountains almost thirty years ago. Soon after I got myself into speleology (ed note: scientific cave studies).

I quickly discovered that there were many caves that had never been explored even in my native Tatra Mountain. They were flooded, and few people were qualified and willing to explore them.

I figured that someone already reached the highest peak of the Earth and even stood on the Moon: If I wanted to be a pioneer, I needed to focus on what had not yet been explored – submerged caves became the obvious choice.

My older colleagues had explored everything below a certain level of technical difficulty, which is why I decided to dig deeper. My scientific mind helped me solve technical issues such as equipment engineering. And to explore safe and efficient enough to enjoy it.

Explorersweb/Pythom: Cave diving is very different from open water diving. It seems almost like mountaineering, you rappel down, “fix the route” with guide lines underwater, there is the use of supplementary oxygen (different gas mixtures), bad visibility and (water) temperatures to deal with, there are The Bends (sort of reverse high altitude sickness), you must save lots of resources to make it back, etc. Have you climbed on altitude? How does it compare?

Krzysztof Starnawski: It’s true that cave diving is by many means similar to alpinism. While climbing, we face altitude sicknesses, such as HACE (high altitude cerebral edema) or HAPE (high altitude pulmonary edema) and while diving, HPNS (high pressure neurological syndrome) or decompression sickness may occur.

Moreover, all the disorders are more likely to develop the higher you climb or the deeper you dive. Their development is just a matter of time at 8000 meters altitude or 200 meters below sea level.

It has been observed that some people are more resilient than others due to factors such as general physical condition, age, mental endurance, mood, or even quality of sleep the night prior to diving.

I find myself somehow predetermined to the endurance. I also deep dive quite often, so I think my organism adapted to the depth. I also take appropriate anesthetics (ed note: a drug to prevent pain during surgery) which considerably decrease HNPS syndromes. We have to take those syndromes seriously, because they may lead to unconsciousness and death.

Explorersweb/Pythom: Walk us through deep dive “acclimatization”?

Before summit attempt, alpinists reach a certain altitude, descend to rest and go up again to acclimate. When it comes to decompression, it is a reverse process.

Humans can’t breathe under water; using breathing apparatus and gas and decompress after diving is essential. It takes me only up to 12 minutes to dive 200 m deep, but 4-12 hours to resurface.

The reason is the diver inhales the gas under the same pressure as ambient pressure. Inert gas bubbles (such as nitrogen and helium) are squeezed and become small enough to easily penetrate all of the diver’s body – neither the respiratory nor the cardiovascular systems are able to stop these tiny bubbles.

While ascending, the ambient pressure decreases and the bubbles expand. I get rid of them by exhaling them but it takes time. During decompression stops I use pure oxygen to accelerate the process. If I quit the stop too early and ascend fast, my blood would behave like a soda can, first shaken and then opened – no one would survive that.

Explorersweb/Pythom: Does weather affect submerged cave divers at all?

Bad weather can become severe jeopardy for alpinists. Water temperature and general environment don’t change that much in submerged caves. There are other issues to deal with, such as unstable cave walls, alternating water currents, decreasing visibility, obstacles you could get stuck in for good…

Breathing gear malfunction remains the most severe hazard though. You could, under certain circumstances, endure a night at 8000 meters above sea level, but no one can survive more than a few minutes underwater.

Of course the temperature itself may be lethal. Deep cave diving we protect ourselves by using dry suits filled with argon (due to the low thermal conductivity of this gas). We also use electric heaters, the very same as those used by winter climbers.

Explorersweb/Pythom: How would you compare cave dives to open water dives?

Open water diving differs from cave diving basically by the fact that in a cave you simply cannot resurface in case of problems.

Moreover, you may experience claustrophobia, and HPNS, which is dangerous in itself, may mess with your mind: It could either cause over-confidence or increase your fear so it turns into a panic attack.

Explorersweb/Pythom: The Hranice Abyss lake stays 15 C year round and never freezes. How come?

Krzysztof Starnawski: This is caused by the geological structure of the cave and the way it was created. Hranicka Propast is not a typical cave.

It was not created like the karst caves, by rainwaters mixed with CO2 eluting the rock crevices. Hranicka Propast was created “bottom-up” by mineralized thermal waters that drilled the rock from deeper to shallower parts, until they finally surfaced.

In a way, this process is similar to volcanoes. Warm mineral waters constantly flow up from below leaving the water temperature in the cave unchanged.

Explorersweb/Pythom: This was a team effort: over the years your expedition mates helped reach 181 meters, 200 meters, 230 meters, and finally 265 meters last year – a dive demanding 8-10 hours of decompression. That’s crazy – how did you decompress for so many hours, practically? And how important are the expedition members for success?

Krzysztof Starnawski: To ascend safely after deep diving I need to decompress. To make it more comfortable, I install a habitat (sort of a diving bell) at about 8-10 meters depth.

My support divers provide food, beverages, additional gas bottles, medical support and rescue if necessary. They also dive down to check if everything is all right with me at the decompression steps.

I always dive alone below 100 meters though.

Almost a hundred people were involved in the project through the 20 years: Polish and Czech divers, constructors, engineers, and my colleagues from the Tatra Mountain Rescue Service.

None of my descents would have been possible without my friends and supporters. Even trivial things like preparing food mattered when I was sitting exhausted by the cave wall after my dive. Yes, this is our team success, by all means!

Tomorrow: Don’t miss the second and last part of this interview, about the final robot-dive to record depths and a mind-ride into closed oceans on other planets.


Vote for Krzysztof Starnawski at National Geographic adventurers of the year


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