Text by Krzysztof Starnawski
Photography by Irena Stangierska
Underwater caves in Quintana Roo state are in about 99% no deeper than 20 m. More often than not their tunnels are on 2 to 15 m. depth and create a spider web like structure.

The Pit and Blue Abyss are one of the few places dropping deep (70m – 110m) and allowing exploring lower levels of caves. At that depth diver is diving in salt water and the salt water would lead to a significant amount of rock corrosion. With two caves in close proximity to each other (about 500 m) one can conclude that they may drop into the same deep collector.

A connection of those two deep caves is very tempting endeavor. This is because each cave belongs to a separate massive cave system. The Pit is in Dos Ojos and Blue Abyss to Sac Actun. A Connection of the Pit and Blue Abyss caves would result in a creation of one continuous almost 300Km system!

From the Pit side few different teams explored cave with mixed results (Steve Bogaerts, Andrew Georgitsis, Patric Widmann, Andreas Matthes). The last successful expedition was completed in 2000 and I don’t think, back then, anybody was thinking about looking for connection at 100 m depth.

My first “tourist” dives in the Pit were done in 2007 and 2008. I had learned this cave pretty well up to the 70m level and I was dreaming to comeback for few deeper dives. In 2009, after few days of preparation, I was able to reach end of line in Next Generation Tunnel and discover a new passage, which I had named Getin Step.

Above:Self portrait of the preparation for a solo dive into Blue Abyss, pity that my team had to leave a few days earlier

Below: Left: A slow decent into the cobalt blue waters ot "The Pit". I always admire the pristine beauty and size of this pit.

Frankly, I laid only 40m of new line, but I also realized that further exploration was in my reach and that this cave has huge potential. This dive took 4.5 hours and was done on a single CCR with 10 bailout tanks. Immediately after surfacing I concluded that with this technique I would not go very far and that Dual CCR construction was in order to seriously think about exploring The Pit. Two thousand-ten was the year of my first attempt diving there with a Dual Rebreather and an addition of new 100 m. What’s more important, passage unexpectedly turned into direction of Blue Abyss. This was the moment when for the first time I formulated thoughts about finding connection. Big passage, running at same depth as Blue Abyss and in correct direction? Why won’t those caves connect???
That was the birth point of new project: “The Pit – Blue Abyss”

First dives in the Pet Cementary (from this cenote is shortest way to Blue Abyss) I had done in 2010. Finding the way to Blue Abyss is not an easy task. Three jumps and over 40 min swim, plus two tight restrictions to reach top part of Blue Abyss hole. In SM, those restrictions are easy to negotiate but with CCR or Dual Rebreather – not so much. Trimix and deco tanks, necessary to explore bottom of the cave, are adding more complexity to the dive. Due to this complexity beautiful cave is rarely visited by divers and an exploration of 70m bottom is even more seldom.

Project just for my dual reb!!! Of course first dives are done in SM, after that single rebreather and at the end, when I felt comfortable in this cave, I switched to dual rebreather. To my surprise, restrictions negotiation was not very difficult. To shorten travel time I decided to use DPV.

End of 2010 is spend on learning the bottom of the Blue Abyss, filming potential restrictions allowing pass to other side of rock collapse, as well as exploring rest of cave to find other deep wells. After 10 diving days, my conclusions were not too optimistic: there was no evident way through. A restriction at 70m appeared way too small for me even in SM configuration and what I could see past it were not too appealing too. I did not find any other deep wells. So in short: complete sh…t .

Above: The King Kong restriction: not too difficult to navigate even with dual CCRs, I pass through it twice a day

Below Left: It’s a 40-minute swim through beautiful cave passages to reach drop of the Blue Abyss

I retreated somewhat disappointed and decided to leave the exploration there for another time.

In March 2011 I came back to Blue Abyss. On my first dive I took another careful look on bottom restriction and decided that definitively was not the way. For over an hour I looked over this rockfall without any results. Another disappointment! Day off and then another attempt (after all, I will not quit after just one try)

Already on very beginning of my search, at 60m depth, I saw a small opening between boulders. I immediately recalled that same place build my interest last year but I completely forgot about it after the dive. Most likely the nitrogen narcosis stressed my memory ;-)!!!

I look over carefully and size it with my hands. Looks like I could pass it with one tank in my hand, what’s more I can see further small chamber allowing me to turn around so exploring this restriction should be relatively safe. Quick glance at my manometers, then a moment of hesitancy and I decide to go for it. I tie off my reel leaving it by restriction and I return on 50m shelf. In 30 seconds my CCR and fins were removed and with two stages in my hands I quickly descent to restriction. No time for unnecessary moves because trimix is depleting fast. I’m leaving one tank by the entrance and with other I negotiate restriction. My dry suit is scratched by rocks but it isn’t too bad. Two meters of bigger space and another restriction; this time opening is slightly bigger. I passed!!! I stabilize the cave line and glance around. Only one promising direction: down, very tight probably with small chance to pass, but I need to try. Not this time, not with one tank but still with no fins to turn around easier in case trouble. I return through restriction with no problems. I just needed to redone my rebreather and I was home free! Of course in my head only because I still have long swim and 2 hours of deco on front of me, but this is piece of cake.

Right: Between serious dive days, I train underwater switching from CCR to SM and than back. This prepares me for the required deep switch.

Photo: Looks like sidemount is the only dive configuration which will allow exploration past the TKM restriction
Sparks of hope flamed when in next few days I was able to negotiate another 15 meters, twisting and turning left and right which lead me into a bigger passage. Another dive, another 50 meters of cave line laid and my head is in a huge collector. “Starnas, once more time you a lucky SOB, all those hours are not for nothing!” I clip strobe to end of line and record azimuths. Three trimix tanks were becoming empty and I decided it’s time to return. A quick survey and back into restriction.

Already on the deco I shared good news with Irena, Mark and Greg who provided support and had my backup tanks so I could complete my trip back and deco if there is a problem with re-donning rebreather.

We all felt very satisfied; this was our first step of conquering Blue Abyss.

Right: I used this little camera mounted on broomstick to see what is past rock collapses in the Blue Abyss

Below: With a large camera, I recorded images of the Blue Abyss’s bottom to help me study for potential exploration leads.

We have an open passageway, but at same time we knew that not much more could be discovered with the OC, after all it’s 70 meters depth – maybe another 100 m on this level with 3-4 stages. Definitely not enough to reach The Pit, that would be around 500 m.

We name huge collector: Nobel Room and passage going to it: Eques. Elusive restriction, when I wasted so much time and my nerves to find and cross, from now on will have a name: TKM (in loose translation: Now Is Our Time!!!)

The Decision was made: we were stopping Blue Abyss exploration and going to prepare for another serious dive in The Pit. This makes sense now since biggest obstacle on way to connect two Sistema, rock collapse In Blue Abyss, is passed!!!

For this The Pit dive we don’t need any special preparation (we trained all aspects during previous explorations) equipment transport, top side and in water support, communication with the caisson are covered. Only difference will be the longer dive time and what I will find past end of the cave line.

I estimated that the dive would take 10 to 16 hours to complete, so we got up at 4AM to be at the syphon at crack of dawn. There wasn’t much talking, everybody knows what to do and, instinctively, we were saving energy for long day ahead of us. The Descent and swim to the end of my last line extension was a piece of cake, after all it was my 6th time there and I feelt at home. Over 25 min with average depth of 100 meters saturated my body with helium and nitrogen pretty well. I attached a reel and started a new extension by slowly following passage going up and down. 30, 60, 120 … line with markers slowly rolled out of my reel.

Unfortunately my progress was hindered by saw like shape of passage and necessity to stabilize line properly. If the cave would follow this pattern then it would be impossible to explore any more during this dive.

Finally after running 200 meters of new line, I reached decision: it was time to go back. It was already late; the line placement and cave survey took more time than I anticipated and a complicated dive profile (up and down) could result with micro bobbles creation.

Right: Hanging on decompression in “The Pit” is a true pleasure, provided it’s still daylight.

I began to be afraid if the end result would be decompression sickness, so I extended deco stops and paid attention to my body looking for any neurological signs.

Finally I reached deco stop at 40 meters depth, Irena and Mark took all of the unnecessary equipment, stage bottles, DPV’s. Once in caisson they supplied me with food and drinks. Previously installed telephone helped very much with communication and safety. Thankfully there were no DCS symptoms and after 11 and half hours I surface safely, just a little disappointed.

It was past dusk, thanks to Mark and Irena all of the equipment except CCR2 was already in our van. Tired, with countless mosquito bites and a little disappointed (with the fact that the passage has not only difficult profile but also is turning shallower) we reach hotel around midnight.

This cave is not giving up easily, not a chance!!! Early morning, when my team was still sleeping, I was sitting on street curb on front of store and drinking sweet coffee from OXXO I analyzed situation. “To further explore from The Pit side I will need support from the Polish Hyperbaric Institute to provide me with a custom deco plan for such diver unfriendly dive profile. For that I need to go back to Poland. Exploration from the Blue Abyss side is impossible due to the depletion of my financial resources, even with the Protec Playa support I have to pay for all helium and oxygen from my own pocket. Gases in Mexico are very expensive and Blue Abyss exploration need to be done on OC since the TKM restriction looks too narrow to pass with a Dual Hammerhead. Besides I will need to find other people to help me (Irena and Mark are returning to Poland in few days. What’s the tough luck!”

The last days together we are spent on taking some footage of well-known, to us, caves and well deserved trip to Mexico’s inland. With a heavy heart I said goodbye to Mark and then few days later to Irenka too, once again saying thanks for all their invaluable support.

Right: My Team of dedicated explorers: Irena Stangierska, Krzysztof Starnawski, Marek Klyta.

Three days of doing nothing and a relaxing trip to Campeche did it. With a clear head again I’m starting to think constructively about cave exploration. “So, why I don’t try to push my CCR through TKM restriction? Ok, even if I’m successful what about bailout tanks? I will need minimum 10 tanks and that isn’t task for one person. It will take way too much time to stage them. So, or I’m waiting until next year, or I need to push my Dual HH on the other side” Crazy idea but I couldn’t stop thinking about it. However crazy it was giving me hopes for further exploration. I quickly sort out what needed to be done: CCR2 modification for an as small as possible footprint as well as ease of removing and re-donning under water. I would need an Eques SM under it so I could push all this “scrap metal” onto the other side. The next night I spent with a needle, scissors and pliers in my hands removing any inessential parts from my rig and shaping the rest for an as much streamlined shape as possible.

Another two days were spend on balancing the rig and learning to perfection: removing and putting rig back underwater as well as pushing my little monster through small restrictions, on the right or left side, with closed eyes and breathing interchangeably from bailout and from CCR. All to have different scenarios practiced before a big dive and all this on a 2m depth and 6 meters from the exit to cenote. It was probably huge attraction for visiting snorkeling groups. By the end of the second day I was quite satisfied and I began to believe in my decision. It is a pity that I’m alone but this I couldn’t change.

I decided for the first serious trail, with a solemn understanding, that in case of any trouble I needed to turn back and end this exploration for now.

As often in life: the better preparation - the better result.

I passed restriction with relative ease and I knew that on the way back it should be same. With the CCR2 “back” on my back for next hour, I explored Noble Room, lay the line and did a survey. With no need for speed, the Dual HH has 8 hours scrubber life, I surveyed different passages and marked those allowing an exploration towards The Pit.

Whole dive took 6 hours, so I had 2 hours to spare.

In the dark I packed my car and alone, I returned to the hotel with satisfaction of job well done. To make traverse I will still have lots of work (after all those are not easy caves) but my dual reb and my team are battle-tested and have something to look forward in future!!!

Exploration Stats.

The Pit:

- new passage “Stairway to Heaven”, 180 m length; total final dive time – 11.5 hours.

- “Getting Step” passage; 70 meters extension.

Blue Abyss:

- Discovery of “Eques” passage and “Noble Room” with total length of 200 meters as well as “extending” this cave from 71 to 101 meters.

Dive Team:

Krzysztof Starnawski - exploration,
Irena Stangierska - support and photography,
Marek Klyta - deep support,
Grzegorz Rutkowski - support,
Andreas Matthes (Protec Playa) - technical and logistic support,

Future plans:

Looks like there is no other choice as to finish what we started. We are looking for financing, modifying equipment, training in European caves and hoping that already in October (latest in November) we can organize next expedition and connect The Pit and Blue Abyss. I think that most difficult parts are past us and all hard work and experience gained so far allow me to look with high optimism to fall expedition.