Lost in a cave

[TSandM]

This is being posted for the person who experienced it, who wished to remain anonymous. Here is his story:

Not too long ago I experienced my first blunder in a cave. Names have been changed to protect those involved. I'm sure we'll get chastised by some because of the mistakes we made, but I'm having this posted because I think it's a good lesson on complacency and the importance of skills and training.

I'm a full cave diver with about 40 dives past full cave, and until the dive in question all of these cave dives were in Florida. I was diving in Mexico with two of my group of Florida buddies: I'll call them Carl and Ed.

Carl is a friend I got interested in cave diving and got him to take Intro to Cave last year. We brought him along on this trip because, despite being Intro-level, his skills in the water are above average for a cave diver with his level of overhead experience.

Ed is a cave & tech instructor who taught both of us, and has hundreds of dives in Mexico's caves, but he had not been down to Mexico in a few years. He was introducing us to the area, a place I had been looking forward to visiting since I started on caves.

The Dive
That morning we drove down to Grand Cenote, our planned dive site. We were briefed on the ride down that we were not going to run a primary reel to the main line because open water divers in this region might follow our line into the cave, so they like to keep the lines hidden from the cavern. We would go in and find the line based on Ed's previous experience. (Do you see where this is going yet?)

We entered Grand Cenote and proceeded to search for the main line: Ed first, Carl in the middle, and me taking up the rear. We found the NSS sign on the left side of the cavern and expected the main line to be nearby. As we searched I regularly kept looking over my shoulder at the entrance, but soon after we passed the sign we lost sight of daylight. We ended up finding a line running high through a tunnel intersecting the one we were in (I figured we couldn't have been more than 50-75 feet from the sign), so we decided to follow that line. I remember watching Carl swim under this line when we came to it (this becomes important later). The line did not look like a main line, though: it was knotted every 10 feet and wasn't the heavy gold line we expected. After no more than 100 feet of following this line, it ended in a section of the cave with dirty water and the line appeared to be broken. Ed pointed out some aluminum cans on the floor of the cave which let us know we were close to an entrance, so Ed tied off his reel and we found another cenote. (After looking at a map later, I think this was called Tul Ha?)

The three of us chatted for a bit and decided that we must be in a side tunnel and swam away from the main line. We decided to turn around and follow this line to the other end, then search for the main line from there since from that side the main line should only be a short jump away. At this point we still had about 2700 psi each in our double aluminum 80's so gas was not a problem. Since we turned around, I led our way back and followed the line as it curved around and ended; I tied off my reel and searched for the main line. I could not see it from the end of this line, so I started reeling out to look for it. I ended up finding a line and tying off on it with the rest of the team following me, but I quickly realized that I tied off onto the same line we were originally on, making a big circle. I explained this to the team and waited as Ed verified what we just did, then we decided to go back up to the other cenote we found to discuss our options. I was trailing the group again, and as we followed the line back I noticed Carl swimming under the line again--I realized it was the same part of the tunnel where we first encountered the line! I looked around and found the tunnel we came in on based on how it had looked when I first saw it, then I laid a clothespin on the line at that point. I caught up to the team and followed them out the cenote.

Ed and Carl started discussing the eventual possibility of having to climb out this cenote and hike back, but I interjected that I knew where we encountered this line and that I was pretty sure I could get us back. Remember, I was sure we weren't more than 75 feet or so from the cavern zone on that line, and we still had plenty of gas (about 23-2400 psi). Carl and Ed agreed to follow me, and we decided on a turn-around point of 1500 psi--if we got that low, we would come back to this cenote.

 

[TSandM]

I tied off my reel to the line we were on and identified the tunnel I found earlier, with Carl and Ed following me. Sure enough, I swam for about 75 feet and found daylight from Grand Cenote again. The team waited in the cavern zone as I recovered my reel and we spent the remainder of the dive exploring the cavern, since our thirds were mostly exhausted. Ed found the NACD stop sign elsewhere in the cavern, and remembered that the main line was close to it. We got fills and came back, ran a reel this time, and found the main line past the stop sign.

What did we do wrong?

* We did not run a continuous guideline to the surface. This was compounded by us being in an unfamiliar system with unfamiliar rules; the cenotes in Mexico are nothing like the Florida springs, so we should have strictly followed the rules we were taught. At Ginnie I've done dives by running a reel in through Devil's Ear and then exiting through the Eye, picking up the reel later, but that experience means little in a place with hidden main lines, low flow and gigantic caverns.
* We took a relatively inexperienced diver with us. This was not a huge problem, but though I think highly of Carl's skill level, I'm not sure if he had the experience yet to do what I did to get the team out if I had not done it. Every member of the team should have been able to do this.


What If...

* ...that cenote had not been there? Could we have communicated effectively enough underwater to find our way out?
* ...that line had not been there? How far in would we have gone, and would we have found our way back without such a solid reference point that I used to start from?
* ...I had not been in the rear on the way in? I'm not sure I would have been looking back as often if there was someone right behind me, since it slows the team down to stop and break the pace in the other positions.


Lessons Learned

* When in doubt, follow the rules. Even if some cave divers in Mexico don't run lines, their familiarity with the systems is probably enough to keep them out of trouble (if it's even a good idea at all). That's no excuse for us to be doing the same thing.
* There's more to being a cave diver than being a line follower. I think back to my full cave exam which asked me to explain the difference between these two. I answered the question by talking about the awareness level that's needed to cave dive safely and not rely on any one thing to get you out (team mate, line, etc.) but now I understand it better than before. Finding the way out like that is not a skill I would ever rely on in planning a dive, but I do feel more confident knowing that I could fall back on those skills when things don't go according to plan (broken line, another team pulling your jump spool by mistake, separated team members, ...). I remember being taught in my cave training to look back every now and then to see what the tunnel should look like on the way out--advice like that makes much more sense now.
* Having lots of gas makes any problem seem less difficult. Conservative gas management is always a good thing. Given sufficient time and gas, just about any non-medical problem underwater can be dealt with, and if you keep in mind how ridiculous of an amount of gas is on your back it makes it easier to think calmly about your options. In a cave as shallow as Grand Cenote (we didn't get past 40 feet) the time we had was even more extended.
* Complacency can strike at any time. The way I see it, unless you follow every rule to the letter there's a small chance on any dive that you'll make an oversight in planning around them. This means that after enough dives a mistake will eventually happen. Fortunately in this sport making one mistake is not instant death: our skills, experience, and reserves give us a chance to recover. To prevent this entirely one can pledge never to violate the basic rules since this virtually guarantees you won't make a planning mistake. To be honest I'm still mulling over which approach makes the most sense for me in my personal diving, but now I do see why these rules are in place and how it's the simplest way to minimize risk.

 

[TSandM]

This was sent to me for posting, and I read it at precisely the right time. You see, several days ago, I was right where these folks were, in Grand Cenote. I was leading a team with two divers who were on their second day of Mexican cave diving ever, and both of whom (and I) are relatively novice cave divers. We had a map to get to the Ho Tul line. I ran line from open water, and ended up on the same line the OP describes, as confused as he was, and we did precisely the same thing they did, by going to both ends of the line. The difference was that we had a guideline to open water, so our dives didn't even begin to register on my sense of what an "incident" is.

It takes very little to turn a dive from a fun experience to something frightening. When I read this, I was acutely grateful for my lack of experience and my very rigorous training, both of which have left me rather acutely unwilling to break ANY of the major rules of cave diving. This story really hit home for me, because I can see how easy it would be to do what the team did, and I can imagine how the three of us would have felt on this weird, ceiling-hung line that went nowhere, without a reference for how to get out.

 

[lamont]

* When in doubt, follow the rules. Even if some cave divers in Mexico don't run lines, their familiarity with the systems is probably enough to keep them out of trouble (if it's even a good idea at all). That's no excuse for us to be doing the same thing.

Isn't that the system where there is a little airdome that you sometimes find snorkelers in and the idea is to drop down there and do a primary tie on the rock right below it? This bends the definition of "open water", but it keeps the line away from the cavern divers, and when you hit your primary tie if you go straight up you can breathe, and you can snorkel out of that airpocket. I can understand that rule because its very difficult to mistake which direction is out there and to swim further into the cave (tip: swim towards the bikinis...)

I can't remember where we tied off there, but we picked up the wrong sign and burned about 20 minutes with the leader not finding the right line, just like the dive above started. However, it was very obvious that the cave was getting narrow and we weren't going to find cave-1 mainline just from the shape of the cave. If I recall correctly, the sign you want is over a bit to the right. So, add "learning to read the cave" to the list of lessons learned.

And I don't know why you'd get advice to not run a line at all...

 

[openmindOW]

Thanks to both the anonymous author and to TS&M for posting. Your post is truly educational; I will send it to some friends.

As for the author's concern that some might criticize, the author should not be attacked. Yes, mistakes were made. If ScubaBoard readers attack authors on the Near Miss Forum for mistakes, that could create a disincentive for divers to post in the future.

By the way, one of the mistakes was made with decent, selfless intentions. The divers did not run a line to the entrance because they did not want OW divers to follow the line into the cave. That was motivated out ofa desire to provide a safer dive environment for OW divers; it was selfless. It was mistake, but the intention was honourable.

Just my 2 cents.

 

[TSandM]

By the way, one of the msitakes was made with decent, selfless intentions. The divers did not run a line to the entrance because they did not want OW divers to follow the line into the cave. That was motivated out ofa desire to provide a safer dive environment for OW divers; it was selfless. It was msitake, but the intention was honorable.

I disagree. There is a reason we are taught to run line to open water. ANY line run into ANY cave is potentially a path for untrained divers to follow; by this thinking, we should never run line to open water, anywhere where people do cavern diving. The unfortunate thing about Grand Cenote is that, if you do run line from open water, you are going to have to cross the cavern line at some point. I don't like doing that, because of the potential for confusion (especially since a lot of the cavern line are gold line, and my reel line is yellow), but the cavern divers should also be following a guide and the rest of the herd, which should prevent mishaps.

In some sites, like the basement line in Dos Ojos, people actually JUMP off the cavern line.

The rule is line to open water, and there's a reason for it, and this story illustrates that reason.

 

[openmindOW]

Fair enough.

 

[Belmont]

A few years ago there was a death when four experienced cave divers got lost on their way back from an alternate cenote. I think it was at Gran Cenote, correct me if I'm wrong.

Thank you for posting this story, it does bring home the importance of the training one gets in a cave diving course and adherence to established protocols.

 

[lamont]

A few years ago there was a death when four experienced cave divers got lost on their way back from an alternate cenote. I think it was at Gran Cenote, correct me if I'm wrong.

They entered from Calimba, which connects to Gran Cenote via the Paso de Legarto line (probably other ways, too, but that's the line they got lost on). It was a double fatality in a team of 4 (with another team of 5? also diving in the system as part of the same group).

 

[Tricia]

"I looked around and found the tunnel we came in on based on how it had looked when I first saw it, then I laid a clothespin on the line at that point."

Wow! Talk about having the right equipment! With my claustrophobia, I'll never do cave diving. But I'm glad to see these guys made it out OK.

Trish