Diving into the unknown: Plura Cave incident Explained
Table of Content
There aren't many places more hostile to human life than a 2°C 135m-deep flooded cave.
This is a story about pushing human boundaries to the limit and going where no one should go. If you like stories about cave diving, then keep on reading, this one is for you!
Pluragrotta
This story starts deep in Norway, in Nordland County. In Rana municipality, there is a valley, by the name of Plurdalen Valley.
This valley contains the Plura River, running more than 27km in length. Whose flow created many underground galleries which are basically flooded caves. One of these so called flooded cave is the Plura Cave, or Pluragrotta. This cave is one of the deepest in Northern Europe, reaching underwater depths of 135m (443 feet). The cave has a length of 3km (1.86 miles) and starts from the Plura River, ending in another dry cave: the Steinugleflaget cave. The high visibility and notoriety of the cave have made it a very popular cave diving destination. The temperature of the water ranges from 2°C (36°F) in the winter to a maximum of 7°C (44°F) in the summer.
It is possible to access the flooded cave from both entry points -from the dry cave Steinugleflaget and from the Plura River- although both pose their own challenge:
From the Plura River: this entrance is the preferred way of accessing the Plura cave, although the main issue is that the surface of the water freezes during the colder months and a hole has to be cut in the ice to actually access the water. Of course, a surface tender has to be present to make sure the water doesn't freeze over while the divers are below.
From Steinugleflaget cave, the dry entrance: This entrance is about a kilometer from the first entrance. To access the flooded part of the cave, you first have to negotiate more than 100m (328 feet) of climbing down, which is understandably tricky to do while carrying scuba gear. For this reason, divers do not really use this entrance.
The incident
Plura Cave attracts a lot of divers and has been dived since 1980, although the traverse to the dry cave Steinugleflaget was only discovered in 2013.
The following story starts on the 6th of February 2014, when 5 Finnish Cave divers attempt to make the traverse from the Plura River entry to the Steinugleflaget dry cave through the 3km-long Plura cave. The group consists of:
- Patrik Grönkvist, 42 years old
- Jari Huotarinen, 40 years old
- Vesa Rantanen, 30 years old
- Jari Uusimäki, 34 years old
- Kai Känkänen, 46 years old
The plan was to split the group into two teams: Patrik Grönkvist and Jari Huotarinen would go first into the cave, followed two hours later by Vesa Rantanen, Jari Uusimäki, and Kai Känkänen, the goal being to meet each other on the other side of the cave. To complete the journey, both teams would have to squeeze through narrow passages, reach a maximum depth of around 130m (436 feet), then do multiple hours of decompression, and squeeze through some more passages to finally exit through the Steinugleflaget dry cave.
The group is experienced and has the appropriate equipment: A dry suit, A Closed-Circuit Rebreather, DPVs, bailout cylinders, etc... Of course more equipment means there is the potential for more failure points, but the divers were well-prepared.
The dive started with the team carving a triangle-shaped hole in the ice layer above the water using a chainsaw: this allowed the first team (Patrik and Jari H.) to penetrate the cave. Patrik is leading, followed by Jari H.
They made their way through the pristine water encased in limey walls, through the air chamber, and the descent (before the deepest, u-shaped part of the gallery) bringing them to a maximum depth of 132m. After this part, while starting the ascent, they would encounter a particularly narrow passage at the 110m mark.
Patrik continues his ascent for a while until he realizes that Jari H. isn't following him anymore. Turning around, he returns to the narrow passage seeing a light move from side to side in the distance, indicating that Jari was in some kind of trouble.
When approaching Jari, Patrik realizes that he is stuck in the narrow passage and tangled in the line. This put both of them in a delicate situation, as at 110m deep, each minute increases decompression time by a significant amount. After a few minutes of trying unsuccessfully to free Jari, the latter tries to switch regulators, but in the process, accidentally inhales water and after panicking, slowly stops moving. Jari Huotarinen is dead.
This is obviously a surreal experience for Patrik, but he doesn't have time to lose as he looks at his diving computer: The decompression time went up from 120 minutes to 400 minutes because of the extended time he spent trying to help Jari. Patrik will now have to spend the next 6 and a half hours in the water to complete all his decompression stops.
The second team (Vesa Rantanen, Jari Uusimäki, Kai Känkänen) goes in around 2 hours after the first one. Everything goes well until the same narrow passage, where Jari U. sees the lifeless body of Jari H. It isn't clear what happened at this point, most likely, upon seeing his body, Jari U. panicked and drowned. At this point, the first team only had Patrik left alive, and the second team had Vesa and Kai left.
Vesa was able to squeeze through the narrow passage past the body of Jari H. Kai on the other hand, did not want to risk getting stuck and decided to turn around, knowing that this would cost him multiple extra hours of decompression, which was still preferable to him not being able to squeeze through and waste more precious time.
Patrik, while completing his decompression stops and wondering what will happen to the other group once they reach Jari H.'s body, sees a light in this distance: this is Vesa's light approaching from the distance. They meet up and end the dive: Vesa skips 80 minutes of decompression because he is low on gas.
After ascending, Patrik and Vesa are now in the Steinugleflaget dry cave and need to climb around 100m to reach the exit of the cave: to not overexert themselves and accentuate the risks of DCS, they decide to wait an hour before starting the exit. Returning to a nearby farm they used as a base for their diving expedition, the direness of their situation was sinking in, thinking they were the only survivors of this deadly dive. However, a few hours later, they would see a faint light approaching the farm: this was the last survivor: Kai Känkänen. The reason he arrived so much later is that his dive ended up lasting over 11 hours, when he reached the Plura river entrance, the hole they had cut up was frozen over and he had to break a layer of ice to be able to exit the water.
All three of them went to the hyperbaric unit to be treated for decompression sickness: only Vesa sustained serious Spinal injuries.
After this event, local authorities, in coordination with three British cave divers -Rick Stanton, John Volanthen, and Jason Mallinson- attempted a recovery of the bodies of both Jari. This was unsuccessful, and after being deemed too dangerous, the operation was called off and access to the cave became illegal. However, the other divers were determined not to leave their friends behind in the cave.
The recovery
It became evident that if they wanted to recover the bodies, they would have to do it themselves. The fact that it was now illegal to go into the cave added another layer of complexity to this operation.
It wouldn't be easy: completing the first dive on its own was not an easy task, but recovering 2 bodies and their equipment from (almost) the deepest part of the cave, while keeping everything under secrecy would be another level of challenge.
This being said, the divers didn't back down in front of the difficulties ahead and started preparing for the operation which consisted of 27 people (17 Finns and 10 Norwegians), including Jari H.'s and Jari U.'s old cave diving instructor: Sami Paakkarinen. The plan was to initiate the recovery from both entry points, with more than 50 tanks spread out between each route. They also had to transport spares of each piece of equipment (dry suits, rebreathers, etc...) to the Steinugleflaget entrance, which included a climb down with the hundreds of kilos of equipment. The main divers conducting the recovery were Patrik Grönkvist, Kai Känkänen, and Sami Paakkarinen. There were multiple safety divers along the main divers and a plethora of surface support personnel. Vesa was not able to go in the water due to complications in his spine caused by the first dive, so he acted as surface support.
The first dive started from the River entrance. As they progress through the gallery, being reminded of their previous dive, Kai changes his mind and announces that he's not in the right mindset to continue the dive, this leaves Patrik and Sami as the only main divers. Less than an hour into the dive, the two divers encounter both bodies. They started by removing Jari H. cutting his equipment and using the DPVs to tow him. All of this goes quite smoothly and the first body is successfully recovered.
The following day, they initiated the recovery of the second body. This time, they start the dive from the Steinugleflaget Cave as it is faster this route. When reaching Jari U., dislodging him and hooking him to an underwater scooter for towing proves to be rather tricky, as his body becomes positively buoyant and almost gets tangled in the lines. Nevertheless, after some minutes of maneuvers, the divers are able to secure the body and initiate the ascent.
The team then decided to leave the bodies in body bags and contact the local authorities to take over the situation. The Norwegian Police didn't press any charges and Patrik Grönkvist received an Order of the White Rose medal for his acts.
Today, the cave is open again to the public and is still quite popular amongst cave divers, although no one is attempting to do the "river to the dry cave" traverse.
Diving into the unknown
The rescue, although done in a secretive manner, was well supported and had a camera crew along with it. The preparation and organization were recorded and there were mounted underwater cameras during the whole rescue operation underwater. All this footage gave life to the documentary "Diving into the Unknown". This documentary uses real footage from the first dive and from the rescue and therefore includes footage of the victims, which may be unsettling for some.
Since it follows and is narrated by the divers involved, we get a firsthand account of the incident that provides a very interesting perspective on the matter.
The Finnish documentary was released in 2016 with a total runtime of 82 minutes. The first part explains the incident and the ensuing failed attempt from the authorities to recover the bodies. The rest of the documentary goes over the rescue mission.
What we can learn from all of this
Of course, as divers, we always want to improve, and my philosophy is to discuss and learn about other people's mistakes to avoid repeating them.
Now, the issue in this situation is that everything was supposed to go well: everyone was a good and qualified diver, everyone had good equipment, and everyone was supposedly in the right mindset to start the dive. Nevertheless, it is still possible for accidents to happen and for bad situations to escalate. We have to keep in mind that the attempt for the first dive is quite an amazing feat, a 5-hour 135m-deep cave dive is nothing to take lightly.
It would be pretentious of myself to try to give advice knowing I am nowhere as experienced as the divers involved in this story. However, if I believe that there is a key takeaway from all of this it's that it is important to be able to recognize troublesome situations and de-escalate them before anything, and more importantly understand that a risk is always present, especially in such a place.
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