Cave Diving, Cave Exploration and Cave Mapping in Yucatan, Mexico
Gran Cenote, Tulum Mexico

Getting Stuck at Vaca Ha!

Wow, the last time I wrote about diving was on December 23.  That feels like a long time ago.  Well, the reason I haven’t written is the diving I am doing hasn’t provided much that I can write about.  I am involved in a resurvey project; Alain and I are collaborating with 2 other fine gentlemen, I am sure you would recognize both of their names if I mentioned them.  Most of my diving has been in the same system laying line and surveying it.  So far we have surveyed 2400ft of cave with an error of about .75%.   We are very pleased with our progress.  Eventually, I will write about in detail.  Now that you have been updated, we can move on to the new dive site I visited today, Vaca Ha.

Patrick and I have been talking about making some CCR dives at Vaca Ha and Tortuga for almost a year.  It seems like the perfect site, good depth and big cave.  Every time we had the time to go, we decided to go somewhere else like The Pit.  Well, I needed to dive somewhere new after a month on the aforementioned project and I decided to hit Vaca Ha.

On Friday night I assembled the breather.  It had been a couple of months since I used it.  Actually, it had been since Patrick’s accident.   It needed a good once over and when I fired it up I found number 2 cell was completely dead.  Luckily, I have a bunch of cells on hand and I made a quick swap.  Everything else checked out.

Since I hadn’t been to Vaca Ha before I needed to get some information on how to access the site and what I should expect.  I called Steve Bogaerts and Bil Philips.  Between the two of them I got the information I needed.  It ends up that Bil Philips mapped Vaca Ha, so I called the right guy.

Vaca Ha Cenote and a Team from Cave Heaven

Entrance to the site is 80 Pesos and the key can be picked up from the land owner, Latacia, in Tulum.  With Bil’s directions getting the key was easy as can be. Vaca Ha is about 5 miles out of Tulum on Coba Road.  Once through the gate drive straight back, don’t take the road to the left, it goes to Tortuga.  The Cenote is a small pool at the edge of a swamp.  It is just big enough for 4-5 people to float around in and do bubble checks.  The guideline starts in open water under the rock overhang.  The pool drops down to 10ft then a smallish cave drops down to 20ft and you enter a minor restriction.  After some tight passage the cave opens up into a beautiful chamber at about 35ft.  Vaca Ha is on the deeper side, my max depth was 76ft and most of my dive was below 50ft.

My first cave dive was up the main line for 35 minutes.  At the 25 minute mark I came to a T.  I took the T left and then came to another T.  I took the T to the right and it ended in a couple of hundred feet.  I turned and checked the other branch; it was going and big enough though I had reached my distance limit for my bailout.  I returned to the first T and checked the other branch, that tunnel was going though it was getting smaller.  I believe it goes to the Strip Tease Restriction and then is too small for CCR after that.  On the way back I checked a couple of the other jumps to the left.  It was an excellent dive.  If you removed the stalactites and stalagmites this cave reminded me of Orange Grove.   Vaca Ha has smooth walls and keyhole shaped passages, very reminiscent.  Maybe it has been a long time since I had been to OG or maybe they are similar.  My first dive ended with out any deco.  It was really satisfying to be on the rebreather again.

On my surface interval I took a 1 hour nap and ate some tuna and an orange.  Not the best tasting combination, but it was food.

Recently, I added half-inch tall d-rings (Manufactured by Steve Bogaerts) to the font of my waist strap in an attempt to get my tanks to ride more level and tighter to the body.  This is a very similar setup to the adjustable rings I use on my sidemount harness for when the tanks get light.  In any event, I used the new d-ring location on the first dive and it really made a difference in the water, I was much more comfortable and I felt more streamlined.  I found the band too low on my tank, so I adjusted up to try and make it ride more smoothly.  It worked well, though I am going to try it even higher on the tank tomorrow.  Moving the clip from the butt plate mounted d-rings to the front of the hips made a world of difference.

On my surface interval I was contemplating where to go next, luckily Adam Korytko from was there guiding.  I asked him and he replied that there is a jump about 13 minutes down the main line to the right and down.  It is marked with a red arrow.  He said it is a beautiful dive and there is a tight restriction.  He wasn’t sure I could pass with the rebreather.  I looked at the team that had just passed it and figured that if they could make it, I could.  I kitted up and hit the water.

Right on schedule I got to the jump.  The jump is down into the halocline and into a short silty passage, so buoyancy has to be the first order of business.  I have to admit that making the requisite adjustments on the CCR and running the spool without a Goodman handle was a little complicated.  I made the jump clean and didn’t add any new damage to the floor.  About 10-15 minutes up the line it doubles back on itself and enters the restriction.  When I arrived I checked my gases and PO2.  I hovered for a minute or two examining the restriction.  It is sort of peanut shaped.  That is if you bend a peanut in the middle and put the concave side down and rock it so it is sitting on the right lobe.  The restriction makes a slight right turn, so unless you enter inverted you have to arch your back to make the turn.  It was deceiving small and a real bender.  After examining it for a minute and taking into account the team that had passed it, I decided I could make it.

I entered the restriction and immediately made contact with the lid of the canister.  Still convinced I could make it, I wigged in a bit more waiting to pop through.  Before I knew it, I was in the middle and couldn’t go forward or back.  The restriction is more then body length and I was committed.  My chest was on the floor and my canister was key-holed.   I slight wave of fear poured over me.  I struggled for a minute.  It was a shock how much larger I was in my rebreather then in sidemount.

I stopped everything and decided to take inventory of my situation.  I checked my access to my bailout regulator and then dumped all the air out of my wing.  It was time to make myself smaller.  The more I squeezed in, the more my counter lungs were compressed.  I held my breath for a minute to listen for bubbles, one of my fears was tearing the loop and being stuck on bailout.  I started to work my way through again moving left and right looking for the biggest spot.  I twisted a bit to try and unhook the canister.  Still stuck I stopped again and decided to think and breathe for a couple of minutes.  I wanted to make my chest smaller and I wanted to confirm the machine was working correctly.  It is easy to loose track of the machine if you are struggling with something else.

I started to list my options: remove my bailout tank to make some more room, remove the rebreather or work on passing the restriction in my kit.  Unfortunately, I wasn’t sure I could remove either piece of kit and the idea of removing the breather and possibly loosing control of the bailout tank scared the hell out of me.  That would be the last resort.

Another minute or two passed and I decided to give it a go again.  I wiggled and then decided to push my chest down and put my face in the floor to try and point the lid down.  POP!  I was out on the other side.  On the other side I hovered for a minute or two to collect myself.  I checked the machine over and decided to exit.  I had had enough excitement for one day!

As you can imagine the exit was no joy.  I got stuck again, however not as bad.  I found a better path through and was able to make myself a bit smaller.  Having passed it once, I was sure I could make it again.

On the exit side, I decided to pass the restriction again to determine the best approach.  As I checked over the machine, I saw one of the 02 sensors was more then a .20 low and stayed that way.  I did a 02 spike to confirm the cell was current limited and it didn’t rise at all.  I held my thumb out, called the dive, lowered my set point to put the cell back in range and did a hearty loop flush to confirm my electronics.  Luckily, the change didn’t negatively impact my deco obligation.  I was relieved I had the cell failure and I didn’t go back through the restriction.  Getting stuck the first time was scary.  The cell failure was worth paying attention too, though not a crisis.  The rest of the trip home was uneventful.

This got me to thinking.  What were my viable options once I was stuck?  I know I had the option to not enter the restriction, so set that one aside.  How could I have made myself smaller or change my shape?  The first thought that came to mind was to try and unclip the lungs and swing them out in front of my so I could push my chest into the ground, though I have never tried this while staying on the loop.  This seemed the least problematic.

The next thought was trying to swim out of the breather.  I wasn’t sure how I could accomplish that and maintain control of the bailout and the rebreather.  There was a drop off after the restriction so there was no place to rest the tank.  And after removing the unit I would be stuck holding a tank and a rebreather in 60ft of water.  I would have to push the rebreather back though the restriction and don it again.  I thought about that for a while and decided I would need a no mount harness to clip the tank to once I was out of the CCR.  I would also need to be able to reach my waist to unclip my harness.  Plus, my weight is on the back plate so I would be positive as soon as I was out of the rig.  That seemed like the least pleasant option short of drowning.

What other options exist?  What have you done in this situation?

I think it is worth while to point out that failures and problems come in clusters! Not only did I get stuck but I had a cell failure.  The cell failure is to be expected, they are at the end of their life span.  I wonder how long the cell had been current limited?  Was it the whole time I was dealing with being stuck and did I just miss it, or did it really happen after I exited?  Remember, “Murphy is a cave diver.”

I am going to give this some more thought and try some exercises under the watchful eye of a buddy.  I am interested to know my options and how they will play out.  I am sure this isn’t my last time being stuck.  If I come up with any good results, I will let you know.


1 Patrick { 01.19.09 at 6:59 pm }

cool story, I wish I would have been there…soon

2 Paul aka Hammerhead { 01.20.09 at 9:42 am }

Yikes! I’ve heard about being “one” with the cave…..but this latest adventure definitely made that relationship a bit more intense.

3 Don { 01.20.09 at 12:13 pm }

Thanks for sharing. Just discovered your site, and your stories are a great read.

4 Anna { 01.20.09 at 8:50 pm }

This scares me Hans. My suggestion – pray like crazy and breath in – or (and this is my favorite) just stay away from the tight restrictions. Interested in hearing the solutions you come up with though.

5 Hans { 01.20.09 at 9:15 pm }

Anna, I had considered not attempting the restriction, though that seemed like the less adventurous route.

I didn’t take time to pray. I didn’t think God was going to intervene on my behalf at that point. And I don’t remember that being apart of any of my scuba training. I will make sure to reach out to Steve and discuss that option.

And lastly, to make yourself smaller you have to breath out. 😉

I am looking forward to seeing you on Friday!


6 Anna { 01.21.09 at 2:31 pm }

Next time then – while your calming your breathing and doing big exhales – say a quick ‘Lord is my Shepard…’ If you’ve been practicing your solutions you should have a spare few seconds for a little prayer. I’m guessing Steve said a few ‘Our Fathers’ after his cave in, while looking for alternate exits. Looking forward to seeing you Friday too – seems like ages!

7 John Katerenchuk { 01.23.09 at 9:14 am }


Of course the cell can fail and become current limited during the dive. One check I do on every dive is to start the dive with as close to 100% O2 in the loop on the surface and then decend only adding O2 to makeup for the volume decrease while descending to 20ft. At that point if done properly the cells should be spiked and reading over your bottom set point. Now I know they are not current limited.

If you do not already do this you might want to give it a try as once you have it done its is a easy check to do.


8 Hans { 01.23.09 at 9:38 am }


Good to see you checking in. Luckily, there wasn’t much published in the last two months so you aren’t too far behind.

To your point, I do check the cells to confirm they are not current limited at the start of the dive. And the cell was fine earlier in the dive. My question was, at what point during my being stuck or preparing for entering the restriction did the cell become current limited? Was it really during the struggle or was it after when I finally noticed?

I would say that the real point of the question isn’t about the cell, but about cognitive narrowing/failure and not being aware of a failure on the machine while struggling with some other “life threatening” situation. I was wondering at what point the failure actually occurred and how much time elapsed before I noticed it. How much time elapsed before my perception widened enough to comprehend what was happening with the machine. I have to admit that sometimes while task loaded, I trust the machine to do its job for a couple of minutes unmonitored. It is why I purchased an eCCR.

Last night I was at the coffee shop with a bunch of divers. All of them were Normoxic Cave divers and some were CCR Hypoxic Cave Divers. As well, they were all tech instructors. One of them is training upto Hypoxic Trimix on OC this week and we were joking about blending gas and the benefits of CCR. It came up that CCR makes it very easy to do very deep dives. You set the machine; you set your X1 and swim around. Nothing to it, right?

The reality is, that it is a walk in the park until something goes wrong: cell failure, loop compromise, break through, electronic failure, solenoid failure, hypoxia, hyperoxia, hypercapnia, user error…). Suddenly, a machine that enabled you to do some really wild stuff is out to kill you and as it does so, it is robbing you of your ability to correct it. Some walk in the park, right?

Thanks for checking in! I look forward to your comments, they are always engaging!