Tragic Incident at Sac Actun Cenote

Incident LocationDiver Names
Mexico, Tulum, Sac Actun CenoteUnknown

On October 17, 1990, a group of eight experienced cave divers entered the Sac Actun Cenote with the intent of exploring this amazing cave system. However, they got into a terrifying situation and struggled to find their way out. Are you enjoying our cave diving stories and not subscribed yet? Please consider subscribing to our Channel. Thank you.

The Sac Actun Cave System

The Sac Actun system, also known as the White Cave in Mayan, is situated nine miles from Tulum. This underground cave system is the longest in Mexico and the second longest in the world. It is unique as it contains over 248 cenotes embedded within it. These cenotes, which are sinkholes, serve as the entryway to the cave, forming this expansive cave system. Within the Sac Actun, you can find animal fossils in large quantities, preserving the history that has been here for several ages. This earned the cave the name “Pet Cemetery.” The cenotes of Sac Actun can be accessed by the public, where they can enjoy the crystal-clear waters and revel in the beauty of nature.

Exploration and Discoveries

Several tourists who have visited the Sac Actun Cenote have engaged in diving, snorkeling, or swimming in the past. Over 215 miles of the cave passages have been studied and explored by different teams of divers, revealing the preserved remnants of ancient history. These archaeological remains include giant sloths, clay pots, jewelry, mammoths, and several animals that existed thousands of years ago.

The Dive Plan

At 10:30 a.m. on October 17, 1990, a party of eight divers arrived at the parking area four miles north of Tulum, Yucatan, Mexico. This group of expert cave divers had planned a six-day trip for group diving, and Sac Actun Cenote was the chosen location. On the fifth day, the diving plan was agreed upon, and a thorough schematic of the cave system was created to guide their exploration. The goal was to enter Sac Actun Cenote, explore the cave, and exit through the Grand Cenote. The planned journey was expected to take 22 minutes, starting at a depth of 40 feet and involving crossing a short 70-foot gap line with a pink direction line sign at the beginning, located around 280 feet upstream from Sac Actun. This gap line would connect with the permanent line leading downstream to the Grand Cenote.

Diving Teams and Temporary Line Installation

The divers were divided into two teams of four members each, and the lead divers would install the temporary line. The first team would retrace their steps to Sac Actun, while the second team would reel in the temporary line once they reached Sac Actun. They would regroup and dive through another tunnel that leads to the third cenote, passing through a formation room and a loop in the passage.

Initial Stages of the Dive

The first leg of the dive went well, lasting only 24 minutes. A second line was fixed and stretched out into the large cavern zone at the Grand Cenote to facilitate navigation down to the cave’s passage. Upon reaching the water surface, they took a 15-minute rest and used that time to review their dive plan multiple times to ensure everyone was clear on the cave structure. Despite their efforts, one team member had difficulty grasping the plan, leading to a third review. Eventually, they descended back into the cave system.

Delays and Challenges

The divers encountered delays along the way. They noticed a crocodile skeleton in one side of the cavern zone, causing an initial delay. Later, a member of the first team lost his mask and was rescued by a member of the second team. After reassembling, they proceeded into the cave zone, with the second team diving closely behind the first team. The first team leader released the reel at the 70-foot mark, the pink direction line marker. As they arrived in Sac Actun, they couldn’t see the second team’s lights and assumed they had a clogged reel. They hoped to sort out the issue as a team and continue.

Disorientation and Tragic Discovery

The first team continued with their plan and reached the third leg of the exploration. However, the leader became concerned about the second team and asked the other members when they had last encountered them. They realized the last encounter was at the pink marker, the 70-foot gap. The first team leader decided to return in search of the second team at Sac Actun but found no trace of them. He went further to the pink marker and discovered that the gap line reel had been switched. Concerned, he then went to the Grand Cenote but found no one there either. He returned to the third cenote, found his group, and they went back to Sac Actun.

Meanwhile, the second team encountered difficulties. At one point, the reel diver on the second team reeled in about one-third of the line when the leader returned and called for him to replace it. They swam back to the pink marker, where the leader turned right and entered deeper into the cave system. The other divers followed without questioning, including the team member who had been mistakenly following the first team. After swimming around 1,000 feet, the leader halted and questioned his teammates using his slate, asking why they hadn’t seen the first team. They decided to turn around and noticed a snapped gap line to the right. Believing it would lead to the third cenote, they followed it for 100 feet, but then saw a line arrow pointing in the opposite direction. Realizing their mistake, they reversed and continued using the main guidelines.

Challenges and Loss

During the dive, one diver’s fin strap came off, causing a brief pause as his teammates assisted him. Although the fins were fixed properly as adjustable ones, they were increasingly anxious as they hadn’t seen a direction arrow for a long time. The two divers at the back, swimming swiftly, passed their teammates and kicked up some silt, disappearing from view. One of them ran out of air and began sharing with the other. They continued swimming, leaving behind a pinstrap and a video camera. Eventually, the first team leader encountered three lights approaching him. The first two lights indicated that the divers were sharing air and were in trouble. The leader found a body hanging from an air pocket in the roof, attempted to provide air, and guided the victim to the water surface.

The other members of the first team had already made it to the surface. However, one member of the second team had not returned. The first team leader and another member dove back into the cave in search of the missing diver. They found him 20 feet away from the first victim, facing up on the floor with his regulator out of his mouth. They attempted to save his life with mouth-to-mouth resuscitation, but it was unsuccessful. Sadly, he had died in the waters of Sac Actun Cenote.

All the divers involved were fully cave certified. The cause of the tragedy was attributed to disorientation, likely due to unfamiliarity with the cave system. In cave diving, even a small mistake or disorientation can lead to dangerous situations or even death.

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What is the Sac Actun Cave System?

The Sac Actun Cave System, also known as the White Cave in Mayan, is the longest cave system in Mexico and the second longest in the world. It consists of over 248 cenotes (sinkholes) that serve as entryways to the underground cave system. The cave system is known for its crystal-clear waters, abundant animal fossils, and archaeological remains.

What discoveries have been made in the Sac Actun Cave System?

Explorations of the Sac Actun Cave System have revealed a wealth of archaeological remains from ancient history. These include giant sloths, clay pots, jewelry, mammoths, and various animal fossils. The cave system preserves remnants of the past, providing valuable insights into the region’s history.

What happened during the diving expedition in the Sac Actun Cenote?

On October 17, 1990, a group of eight experienced cave divers embarked on a six-day trip to explore the Sac Actun Cenote. During their dive, they encountered disorientation and became separated. Tragically, one diver lost his life while another went missing. Despite their certifications, the divers’ unfamiliarity with the cave system contributed to the unfortunate outcome.

What challenges did the divers face during the expedition?

The divers faced various challenges during their expedition. These included encountering a crocodile skeleton, losing a mask, delays caused by equipment issues, and disorientation within the cave system. These factors combined to create a dangerous situation, ultimately leading to the loss of one diver’s life.

What lessons can be learned from the tragedy in the Sac Actun Cenote?

The tragedy in the Sac Actun Cenote serves as a reminder of the importance of cave diving expertise and familiarity with the environment. Even experienced divers can face dangerous situations if they are not adequately prepared. This incident highlights the critical role of thorough planning, knowledge of cave structures, and effective communication in cave diving to ensure the safety of divers.

Patrick Broin
Patrik, a seasoned cave diver, shares his first-hand experiences and expert insights on the treacherous world of cave diving accidents.
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