Devil’s Eye Tragedy: The Unfortunate Fate of Diver Carlos Fonseca

Devil’s Eye Tragedy: The Unfortunate Fate of Diver Carlos Fonseca
Incident LocationDiver Full Name
USA, Florida, Gilchrist County, Devil’s Eye CaveCarlos Fonseca

The Devil’s Eye system is one of the most popular and frequently dived caves in the world, but only certified cavern or cave divers with dive lights are permitted to enter. If you are not careful enough, this cave can be very life-threatening. That’s what happened with Carlos Fonseca. He was a good diver, but because of his own negligence, he got into big trouble.

Description of Devil’s Eye Cave

The Devil’s Eye is a cave located approximately 10 minutes west of High Springs, Gilchrist County, Florida. The cave is part of the Ginnie Springs resort complex and has two entrances: Devil’s Eye and Devil’s Ear. They quickly join each other underwater in the gallery, which is a wide tube. In general, Devil’s Eye provides faster and easier access to the cave system. It is a round opening, 20 feet across and equally deep, with over 30,000 feet of mapped passageways. Divers can spend a lifetime cave diving, and yet there is a big part of it that is yet to be explored. But it is as amazing as it is scary because it is also called the “Killer Cave” since it has claimed 28 lives. That’s why only certified divers may enter the cavern and explore as far as they are able to see using the present sunlight.

Carlos Fonseca’s Background and Passion for Diving

Carlos Fonseca, a resident of Caledon, Ontario, made diving a way of life. His dedication brought him many wonderful experiences as well as wonderful friendships. His passion for exploration and the search for the unknown led him to Great Lakes Technical Divers or GLTD, allowing him to pursue his dream. Carlos was an active trimix diver, full cave diver, and sidemount full cave diver. His most famous accomplishments include receiving the National Association of Cave Diving Wacolo Ward and establishing Great Lakes Technical Divers as a co-producer of the “We Are Water” project.

Dive Preparation and Arrival at Devil’s Eye Cave

On Thursday, August 8th, 2013, Carlos was about to go for a dive within the Devil’s Eye cave with a couple of his teammates. They drove for an hour from their county and reached their destination. His teammates were a couple of his friends that he used to dive with almost all his life. His friends used to brag about this guy because Carlos was living the best days of his life. He was healthy, rich, and had all the time in the world.

Negligence and Equipment Issues

Carlos was preparing an aluminum 80 cubic foot tank labeled O2 and MOD 20 (maximum operating depth 20 feet) as a stage bottle to 90 feet to extend his penetration distance into the cave. He and his teammates decided to go into the cave turn by turn. Carlos was an expert at diving, so obviously, he was going to lead his teammates. Whenever he and his mates were on vacation and decided to go for a swim, Carlos was always the one to lead.

When they were getting ready, his teammates noticed that he was about to use an oxygen bottle at a depth greater than what was safe, and they questioned him about it. As indicated, the oxygen bottle was designed to be used down to a maximum operating depth of 20 feet. Carlos, who had a full mix and blend station at home, responded that he had filled the bottles himself and was aware that they were full of air. But little did he know, Carlos’s colleagues expressed concern about the tank, which they suspected was not filled with sufficient oxygen, and he insisted that he knew it was air.

Dive Plan and Entry into Devil’s Eye Cave

The team continued to prepare for the dive by discussing the dive plan, reviewing the map, and making emergency and contingency plans to turn the dive if necessary. Carlos proposed that no visual jumps would be made during the dive, which refers to crossing a gap without a gap spool between the main permanent guideline and where a branch line begins. The team entered the Devil Springs cave system via the Santa Fe River’s eye.

Tragedy Strikes in the Cave

The initial 20 minutes were a smooth dive with no apparent mishaps. Carlos was leading the way, and his teammates were just behind him. They stopped to take pictures for a couple of minutes and kept on diving further. As they were diving, the oxygen levels dropped, and at that time, they should have checked their oxygen tank levels, but they didn’t. They had gone about 400 feet upstream and were about a third of the way between the park bench and Hill 400 when Carlos began to have seizures and then lost consciousness at a depth of about 85 feet.

The partial pressure of oxygen was about 3.6, resulting in oxygen toxicity. Oxygen toxicity, also known as oxygen poisoning, is lung damage caused by inhaling too much supplemental oxygen. Too much oxygen can be harmful to lung tissues, causing them to collapse and making breathing difficult. In severe cases, it can even be fatal.

An easy way to think of partial pressure in scuba diving is to consider it a measurement of the concentration of a particular gas in a diver’s mixture of breathing gasses. As the concentration of a particular gas in a diver’s breathing gas mixture increases, the physiological and psychological effects of that gas may increase or change. For example, extremely high partial pressures of oxygen may be toxic (oxygen toxicity) and very high concentrations of some gases, such as nitrogen, may cause narcosis.

Two factors determine the partial pressure of a gas in scuba diving—the percentage (or fraction) of the gas in the breathing mixture and the depth (and therefore the ambient pressure) at which a diver breathes the gas. The higher the percentage of a gas and the deeper a diver descends, the greater the partial pressure of the gas.

Rescue Attempt and Carlos’s Death

As the group surfaced and yelled for assistance, other divers, including cave instructors, assisted in bringing Carlos to shore and began CPR. Carlos was taken to the hospital alive but later pronounced dead. Journalist and fellow diver Robert Osborne wrote about his friend’s death in The Huffington Post. Before the news of Fonseca’s death was made public, dive forums picked up rumors and spread a story about him dying while exploring Devil’s Spring.

Reflections and Lessons Learned

After his death, questions arose from all around because Carlos was quite an expert, so nobody could have ever expected him to be gone, especially while diving, which he was considered an expert at. His friends and relatives were all there, trying to process what had happened. His friends were shocked because how can someone make a mistake in something he has been doing for years?

Carlos’s health was not the issue; he was a healthy person without any known health issues. However, several other factors led to his demise. First, the oxygen tank had insufficient oxygen. His teammates indicated that the tank was not fully filled, but they should have insisted on checking if the tank had enough oxygen or not. Nobody at Carlos’s home had any idea of him even checking the tanks, let alone preparing for a dive that would probably end his life.

Secondly, although the planning of this dive was right, Carlos was overconfident that day. Carlos and his teammates had been planning this dive for years, and they came well prepared. However, that day just wasn’t their day, and Carlos was overly confident. Cave diving is regarded as an extremely dangerous activity due to the sheer number of risks involved.

Another mistake Carlos made was holding his breath more than necessary. This is a crucial diving safety rule, and failure to follow it could result in death. Holding your breath underwater at depths scuba divers reach can lead to lung damage, known as pulmonary barotrauma, and in severe cases, air bubbles can escape into the chest cavity and bloodstream, causing arterial gas embolism, which can be fatal.

Every dive site is unique, and conditions such as weather and current can vary significantly. Thorough research is necessary before considering entering the water and diving to great depths. Checking current conditions, ensuring equipment is in proper working order, and being well-trained for the conditions and depth of the location are essential for safe diving.

In conclusion, the Devil’s Eye tragedy of Carlos Fonseca serves as a reminder of the risks involved in cave diving and the importance of adhering to safety protocols. Even experienced divers must exercise caution, conduct thorough checks, and never dive without proper training. Cave diving can be a thrilling and awe-inspiring experience, but it requires meticulous preparation and respect for the inherent dangers of exploring underwater caves.

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Is Devil’s Eye Cave safe for diving?

Devil’s Eye Cave can be very life-threatening if proper precautions are not taken. Only certified cavern or cave divers with dive lights are permitted to enter.

What is the depth and size of Devil’s Eye Cave?

Devil’s Eye is a round opening, 20 feet across and equally deep. It has over 30,000 feet of mapped passageways.

How many lives has Devil’s Eye Cave claimed?

Devil’s Eye Cave, also known as the “Killer Cave,” has claimed 28 lives.

What were the factors that led to Carlos Fonseca’s death?

Factors that led to Carlos Fonseca’s death include insufficient oxygen in his tank, overconfidence, and holding his breath underwater.

What lessons can be learned from Carlos Fonseca’s tragedy?

The tragedy highlights the importance of thorough equipment checks, caution, proper training, and respect for the dangers involved in cave diving.

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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