Tragic Incident: Amy Maria Arriaga’s Fate in the Sac Actun Cave System

Incident LocationDiver Full Name
Mexico, Quintana Roo, Tulum, Gran CenoteAmy Maria Arriaga

Today’s cave diving story reveals one of the scariest scenarios cave divers could face – losing sight of one of your teammates in one of the most dangerous cave diving sites in the world

This tragedy is about Amy Maria Arriaga, who went for a dive in the Gran Cenote. This cave is located three miles (five kilometers) from Tulum center in southeast Mexico. The entrance is right next to the parking lot. Gran Cenote is relatively easy for swimming and snorkeling into the caves for a spectacular view of the light beams hitting the water through the cave opening and checking out the rock formations. Divers can explore the rock formations via a series of caves with white walls. Despite what the name would imply, this cenote is really made up of numerous smaller ones that meander over the lush forest floor and are connected by wooden walkways.

A cenote is said to be very important to the Maya civilization. While cenotes were their primary source of water, they were also thought to be the entrance to the Xibalba or underworld and a place where the Mayan gods would visit, particularly Chac, the Mayan god of rain, lightning, and thunder. This means that cenote systems are beautiful yet also scary and dangerous. Some parts of the cenotes are very dark, which can alter your sense of orientation, therefore you could easily get lost. Until now, the Gran Cenote has claimed five lives.

Amy Maria Arriaga

Amy Maria Arriaga, a Bakersfield resident and a teacher by profession, was born on December 17, 1977. She always had a passion for diving. All the friends she had from a very young age were occasional divers. Amy taught for 13 years in Wasco. She taught 5th and 6th grades English and seventh-grade science. For the last three years, she was very inspirational according to her students. Her unwavering devotion to her family was undeniable. She went to her father’s house every day to check on him because Amy’s angelic mother, Mary Arriaga, died two years ago on October 18.

Amy made sure her father, Tom Arriaga, felt loved and cared for after her mother died. She was extremely proud of her father and frequently boasted about him to all of her friends. On November 26, 2016, Amy and her friend Alessandro Morano went on a fun dive in the Sac Acton cave system. They started at Grand Cenote and would return to the same point. She asked Alessandro to take photos and videos of her during the dive to show her friends and family back in the United States what she was doing. Alessandro taught her Open Water Sidemount course and the Full Cave course, as well as a day of Intro to Cave course refresh plus all the cave course dives. She performed very well and completed the training on November 24, 2016. Quick reminder, she completed training two days before the dive we are about to discuss sidemount course and the full cave course, as well as a day of intro to cave course refresh, plus all the cave course dives she performed very well and completed the training on November 24, 2016. Quick reminder, she completed training two days before the dive we are about to discuss.

Dive Plan

For this dive in the Sac Actun cave system, it was explained and agreed that Amy would always be diver number one, whether the loop was completed on a single dive or not. The plan was to follow the upstream line, at the end of which they both agreed to use a reel to connect to the Cuzanot jump line and then another jump to the right to connect to the end of the loop line. They agreed that if they reached the Cuzanot jump line using the rule of thirds, they would remove the jump and follow the line to the exit.

Training and Reminders

Alessandro did remind Amy how they would proceed in the circuit during the dive briefing, just as she had practiced on the last days of her cave training, such as on the circuit in Cenote Minoturo on the 23rd of November. Alessandro also reminded Amy that the Cenote Hotel, which is located very close to the beginning of the Cuzanot loop gap, could always be used as an emergency exit by divers and that the cenote could be located by the natural light coming through the synod opening. Further ahead on the left, there is another small cenote called No Name, which is not as easy to spot from the line as the Cenote Hotel but can be seen by covering the primary lights. They agreed on a maximum depth of 40 feet during planning, and if they didn’t reach their jump reel installed at the beginning of the loop using one-third of their gas, they would turn around and return using the same line used to enter the cave. Amy did check her tank’s pressure and made notes on her slate about the return pressure, estimated time, and depth.

Dive Start

They did their gear check on the surface, and Amy agreed to be the dive leader for the duration of the dive because Alessandro was filming the videos for her. The dive did begin at 11:26 am. Alessandro installed their primary reel from open water around the cavern line to avoid disturbing the cavern tours because they were the first team to enter the cave, and there was no other line connected to the cave line before theirs. Alessandro hung a cookie on the line and instructed Amy to take over as the leader, as agreed upon during the pre-dive planning.

Navigating the Cave

For those of you who don’t know what a cookie is, it is a personal marker, also called a REM marker, which is placed on the line that divers use between intersections. It is used to ensure that the team leader is leaving no one behind. They placed a cookie, confirming their exit minutes later when they arrived at the arrows in both directions, where the line does a 90-degree angle and has the Paso del Legato jump.

They arrived at the line gap a few minutes later, around minute 25 into the dive, and Alessandro showed Amy the natural light coming from the Cenote Hodel. At this point, she did ask Alessandro for the gap after checking her air supply, depth, and time, and Alessandro responded with the go-ahead signal. Amy connected the gap, and Alessandro installed a cookie with his initials, canceling the arrow at the end of the line and starting the lay line towards Cuzanot loop. Amy connected the line and placed a cookie on it.

They arrived at the loop jump a few minutes later, and at the loop jump, Amy again checked the air pressure, time, and depth before asking Alessandro for the jump, to which he agreed. Amy added another white arrow with her name before the cave arrows, this time with her jump orange line attached. She connected her line straight to the end and start of the loop line, installed a cookie, and waved back to Alessandro, receiving an OK signal back. They began to follow the loop line counterclockwise.

Alessandro asked Amy for her pressure when they arrived at the double arrow pointing the closest way out, to determine if they needed to mark it or if they could complete the loop in a single dive. She replied that her pressure was 2300 and 2200 pounds per square inch. Alessandro’s pressure was similar, and she instructed her to proceed as planned in the pre-dive planning. When they passed the Cenote No Name sign, Alessandro tried to call her attention to take a video of her. However, he covered the lights to be able to see and video record the natural light coming from the cenote.

Amy’s Disappearance

At that time, they had the cave line on the left and the No Name cenote on the right. Amy was between Alessandro and the wall. But when Alessandro looked around, he couldn’t find Amy or see her light, making a 90-degree turn in the line around a formation blocking the view. Alessandro did swim around, expecting to see Amy just around the formation. Alessandro followed the line, assuming Amy was ahead because he hadn’t seen Amy when they arrived at the jump line. There was still no sign of Amy, but she had followed the line out and left the jump to be recovered by Alessandro, as planned. Alessandro stood there for two to three minutes, waiting for another chance to lay his line, but there was still no sign of her.

However, Alessandro did recover the markers and line because he was confident she was ahead, as they just discussed in her training. She should not stay searching for too long because the other diver will usually be outside, so she should never jeopardize her safety on the jump. They had another jump reel with a yellow line installed next to theirs, both connected to a REM marker or cookie from the opposing team. Alessandro’s big mistake was removing their reel and the cookie. In his mind, he was certain she was ahead of him. At the time, Alessandro removed the gap reel and cookie while leaving the primary reel in place because he needed to know if Amy was okay outside as soon as possible because he hadn’t caught up with her yet.

Alessandro went back to the surface to look for Amy. He saw some lights outside the lake and thought it was Amy, but it was just another couple getting ready to dive. Alessandro asked them if they saw a blonde girl with a blue helmet, to which they replied yes, they saw a girl. Upon asking where she went, they asked to follow the shortcut that led to a hotel in the cave. Alessandro went straight down there but when he arrived at the cenote entrance and looked for her, she wasn’t there. Alessandro exited the water and began looking for someone with tanks to borrow. He got his cell phone and tried to contact a fellow diver, Fernando, but the call didn’t go through. So he left his cell and picked up his keys with a guide and got one of his tanks, the left one with 3000 psi, and the right one from one of the team members, which had around 2300 and 2400 psi.

Discovery of Amy’s Body

At this point, it was around 1:47 pm. Alessandro went down alone around 2:13 pm and followed the same route Amy had planned, connecting the gap, jumping, and installing the markers, this time with the permanent marker. He went counterclockwise around the loop, just like Amy had planned. After the restrictions very close to Cenote No Name, he discovered Amy’s body facing up, lying on her back near the line, with one of her cookies installed beside her. The regulator was not in her mouth, and the tanks were empty, but the mask was in place. Alessandro unhooked her mouth and inserted his long hose into her mouth, attempting to push air down. She didn’t say anything and had some foam coming out of her mouth. Alessandro dragged her head out of the water and sand, removed the helmet and mask, and attempted resuscitation, but she didn’t respond.

Two backup divers arrived, and one of them attempted CPR as well. Then a third diver arrived, a side mount diver claiming to be a former rescue diver who wanted to assist. He gave instructions and asked Alessandro to follow him while the other guys carried the equipment out. When he arrived at the jump, he lost buoyancy, and one of Amy’s fins became entangled in the cave line. Alessandro then asked the diver to let him handle the body and to follow him. He agreed, and Alessandro returned the body to the Grand Cenote.

Aftermath and Investigation

After 35 minutes of diving, Alessandro surfaced and summoned the cops while his fellow instructors waited. At that point, he handed over the body to the authorities and waited to give his statement. The police arrived, took the body, and sent it for autopsy. Alessandro was asked a few questions, which he answered correctly as the investigation went by. It was revealed that Amy had deviated from her path and ended up in a dark cave, having no light. She tried to go back the way she came but got lost again. Her oxygen level in the tank dropped, and she was gone for good. After a while, it was 20 minutes before Alessandro found her lifeless body.

This was the tragic story of Amy Maria Arriaga on her first and unfortunately last cave dive after completing her training.

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What was the location of the cave dive incident?

Incident Location: Mexico, Quintana Roo, Tulum, Gran Cenote

Who was the diver involved in the incident?

Diver Full Name: Amy Maria Arriaga

Where is the Gran Cenote located?

he Gran Cenote is located three miles (five kilometers) from Tulum center in southeast Mexico, with the entrance next to the parking lot.

How many lives has the Gran Cenote claimed?

Until now, the Gran Cenote has claimed five lives.

What led to Amy Maria Arriaga’s disappearance during the dive?

Amy deviated from her planned path and ended up in a dark cave without light. She attempted to go back but got lost again, and her oxygen levels dropped, resulting in her tragic loss.

Rebecca Penrose
Rebecca, an experienced blogger, delves into the world of diving accidents, sharing insights, stories, and valuable lessons learned. Dive in and explore the depths of underwater safety.
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