Sac Aktun at Gran Cenote

January 25, 2007. Without any doubt, Sac Aktun is my absolutest, bestest, most fav'rite place to scuba dive in all the wide world. Sac Aktun also gets credit for being the #1 motivation for getting my Full Cave certification for many reasons, the most explainable being that it has been photographed so much that I couldn't help but fall in love with the place even before I dove there the first time. But that's another story for another day.

Pictures here, for now.

Thursday was my third dive trip to Sac Aktun, the second trip with a camera, and the first time without a paid guide in this cave. My partner was Glenn, a bicycle shop owner from Cincinnati. The two of us met through German Yanez, and we'd done other dives together over the past two weeks. Our decision to go without a guide was based on two factors: (1) cost: with a guide it is $145 each for two dives and to do it ourselves came out to about $72, even including car rental and ferry crossing; (2) relative confidence: we'd dove Sac Aktun a week previous and knew generally where we were going. We did a lot of homework before the trip and made solid plans for our dives the night before. There is a saying in cave diving that goes "plan your dive and dive your plan." Good philosophy and it served us well.

The day before we met at The Coffee Bean in Cozumel. This turns out to be my first (and fortunately, only) bad decision in hindsight. I've decided that The Coffee Bean is passively trying to get me killed (read this lightly as a JOKE, please) as their coffee must have 3 times the normal amount of caffeine as anywhere else. I had one iced mocha at 3pm which should have washed through my system by bedtime. Nope! I had a totally sleepless night, not a good thing before going on a tec dive. The last time this happened was... unfortunately... during my full cave class which of course was much more critical. On that day we were having evening class at The Coffee Bean and I asked for 'cafe hielado, descafeinado por favor!!' and when it arrived tried to confirm with '?esta descafeinado?' and got the affirmative from the waiter. Half an hour later, the freaky and all too familiar caffeine buzz came over me and though I tried to detox by drinking a whole gallon of water before bedtime but to no avail. It was a sleepless night and the next day's cave class with moderate sleep dep.

Anyway, I'm getting used to cave diving with no sleep and in truth it didn't effect my performance, safety or enjoyment as far as I can tell. But did I ever sleep like a rock Thursday night!!

7:45am: Met Glenn at the ferry terminal. First expense is MX $110 (US$10) for the ferry crossing to Playa Del Carmen. Winds were heavy and the local ports had closed traffic for smaller boats... too bad for many dive operators on Cozumel. The Belinda (my usual dive boat while on Cozumel, through Aqua Safari) couldn't go out. Oh well, perfect day to go cave diving!

8:45am: Ferry landed, it was surprisingly smooth trip, very little tossing and no sick passengers. I don't get seasick myself, but you know, if someone next to you loses it, it doesn't make you feel very good. Anyway, we collected our dive gear (careful with that camera!!) and trudged the six blocks to the Hertz satellite office.

9:15am: At the Hertz main office we get our car, a light blue Chrysler ATOS nearly spankin' brand new with only 1023 km on the odometer and just a single paint scratch on the right front wheel well. Hertz doesn't try to hassle with me on insurance and the agreed rate is MX $340 ($31). Nice. Off we go.

10:30am: Arrive at Sac Aktun after picking up tanks along the way. The entrance fee is MX $100 (or US$10) and after only a little hassle we are allowed to drive behind the fence to the tables closer to the cenote. We had picked up two sets of doubles and a single 80 cf tank that I will use as a stage bottle on the first dive. Glenn's air consumption is lower than mine, probably because I am blowing a lot of air with the camera the whole dive. (Better to use up some air than to have bad buoyancy control, I say.) The stage bottle will be my main air source for the first dive which also makes air planning easy. My turn point is when the single stage tank is empty, that's 1/3 of my air.

There are two other dive teams here and we ask them about their plans to see if we'll have any conflicts. One 3-person team is going our way, to Cuzan Na loop, with a video rig 3x the size of my DSLR. That's also our dive plan so we'll have to watch for them on the way in. The other team is going to Paso del Lagarto which we'll be doing our 2^nd dive so no worries there.

11:00am It takes Glenn inexplicably longer to get ready than any other dive partner I've had in the past so the other dive team is a good 20-30 minutes in the water before we finish our equipment matching and S-drills. For the S-drill I took the camera to make sure it could be clipped so as not to interfere with the long hose (successful!) but left the stage bottle on the dock. I clipped on the stage bottle, deployed the hose and off we go. Joy! Bliss! Cave Beauty!

Sac Aktun is unlike other cave systems in so many ways, one of the first remarkable things is how welcoming the cave seems from the outset. Beautiful columns of formations are just inside the cave mouth and all along the the tunnel as we lay our line from the cavern line to the main line. It's almost as if Sac Aktun is silently telling me "You're very welcome here; I really want to show you my beauty and have you treasure it." The dive team that went to Lagarto passes us on the way in; I guess they called the dive early or had some problem. Either way there's only one other line into the cave that we parallel as we go in. Down we go, Glenn in the lead running the spools and markers. (This was agreed the day before, if I had to rent the car and do the driving, the least he could do was lead the dive.)

Our plan is to go to the Cuzan-na / Lagarto split and observe where the jump to Lagarto is, mark our passing with a cookie but continue on the main line on to Cuzan Na (Cuzanah?) and set up a circuit on the loop, then depending on conditions continue on the circuit to the right (counter-clockwise) or retrace and do the loop clockwise, retrieving the reel on the way out. Total dive plan: 90-120 minutes, turn on air is Glenn's 1/3rds which is a magic number of 900 psi.

Along the mainline we pass someone's jump line where I'd never seen one before and later I realise that this is the shortcut (very long jump) to Cenote Ho Tul. We're taking the longer way 'round to the same place, but that's mostly because I'd never done that jump before and that we wanted to look at the Lagarto jump before we did it.

Sure enough as we get close to Cenote Ho Tul we pass the spool end of the jump. The video team is just ahead of us. I had studied pictures from our previous dive as to where the jump across Cenote Ho Tul looked like, so I was watching for it. Also, we should have seen the other team's jump spool at that point so we could lay ours. HOWEVER, the other team failed to place an arrow at their jump and their line looked identical to the mainline. We don't fully realise this until we reach their jump spool. Glenn is confused by this and I realise that the tie-off was indeed some ways back -- not our error, really, but bad protocol by the other dive team. Back we go and we lay our line properly, with arrow, at the end of the mainline. As we cross Ho Tul with our own spool the other dive team is coming out, retrieving their reel. We wave anyway (no use getting pissed at someone else's ignorance, really) and onwards we go.

The Cuzan-Na loop is not too far from there but when we get there the right jump is badly silted up -- why do camera crews always do this? Its bad enough to see open water photographers ripping up the ocean reefs, but in a cave it is much worse! Cave formations (speleotherms) do not grow back!!! Ever!! More curses, short lived, but it is now up to Glenn to decide on the plan. He is undaunted by the silt and low vis and made the same decision I would have... lay the jump through the silt and proceed in the counter-clockwise direction of the loop with the assumption that the vis will clear soon with the downstream flow as we are still heading upstream. Good guess and we're soon back in 200 ft vis just in time to view the Cuzan-na Room (our previous guide referred to this as the Crystal Palace) in all its amazing splendor.

This trip was my first time ever diving with the 10-22mm wide-angle lens. I made this decision specifically for this room, which must have 3,000-5,000 stalactites of all imagineable sizes. Unfortunately, I don't have a zoom gear for this lens... not yet anyway, it should be in my hands on Tuesday. So I had to make the problematic decision to fix the zoom at 10mm before the dive and live with it, hoping that there would be enough flash from the single strobe to cover such a wide angle. As it turned out, this worked GREAT and I now have relatively nice pictures of the Cuzan-na room... as well as everything between there and the entrance.

I think that alot has to be said for Canon lenses. This 10-22mm lens has a f/2.8 which isn't the strongest for this kind of work, but you can tell just by looking at the size of the optics that the light gathering power of this lens will be superior. And indeed I am very pleased with the results. There is some vignetting which is expected with such wide fields of view. There are also focus problems at the outermost edges but I don't know if this is caused by aberration due to the dome port or maybe my f-stop needs to be lower. More dives will tell me which it is.

Our way out of the cave is uneventful; I'd been using the stage bottle the whole dive but switched over to my back gas about 500' from the entrance when I reached 500 psi. Though I am sure I wouldn't panic when the regulator suddenly pulls hard, its not a good idea to drink a tank dry if you don't have to. We are taught as open water scuba divers to leave pressure in the bottle or risk getting water seepage into the tank, potentially damaging the tank and your regulator.

12:40ish'pm We surface at Gran Cenote after 98 minutes of total time. Very satisfying dive in all respects. We decided earlier in the day not to leave site and buy lunch in Tulum like we did on our guided trip because we weren't sure if the trolls at the gate would charge us a second time. Also, since Sac Aktun is a max. 40' dive (average 32-35' for whole dive) there is not so much concern about nitrogen uptake on such long profiles. But to be extra safe we had done a good 6-7 minute safety stop @ 12' in the cenote before surfacing. Fun time to play with all the freshwater fish that are all around us like flies.

It is pouring rain as we exit the cenote. Never a dry moment, I guess. In a way I welcome it because it means that the mosquitoes will be kept at bay. They aren't horrible today, but since my cave instructor came down with Dengue Fever two months ago which put him out of commission for 10 days, I've been extra concerned about mosquito exposure. Especially because I forgot to bring bug juice with me this trip.

The rain is timed perfectly; it kept us cool as we do the long climb out of the cenote in our 6 mil wetsuits, but it pretty much ended in time to start eating lunch and talk about the dives.

2:00pm Our second dive is planned to make the jump to the beginning of Paso del Lagarto line and keep going until one of us calls the dive, or until we reach a 'T' which probably means we reached Much's Maze. Into the cave we go. Beautiful! I hope I never get used to this, the spectacle of Sac Aktun always strikes me as if it were made of magic.

Neither of us have been this way before but the jump seemed kind of obvious on our previous dive. Glenn starts laying reel in the assumed direction but the beginning of the line is actually a slight dogleg to the right from our guess. No problem, plenty of tie-off opportunities and it follows all the protocols. At the beginning of the mainline there is a handwritten sign, one side in English the other side in Espanol stating that because of construction at Cenote Calimba, it is not advised for divers to go near there as the area may be unstable or impassable. I had read about this a few days before on the QRSS website but didn't think to mention it to Glenn before the dive. He was visibly concerned after reading the note but I conveyed to him it was okay and we should continue. We would be getting nowhere near Calimba, not with the amount of air we had.

This upstream passage is narrower, cozier, than Ho Tul. Formations are still regular, various, and everywhere. But the character of the passage changes more often and we come across areas where it is more honeycomb-like which may indicate where the underground river was more vigorous at the end of the ice age, etching its way through the limestone.

We go a long way following the guideline and have no indication of any turns, jumps, or side passages along the way. Just one round cookie with no writing on it in a place that made no sense. Maybe this was a turn-around point between Calimba and Gran Cenote? Dunno, but since it wasn't a directional marker and seemed to have no other meaning we just ignored it. The way ahead didn't change and we were clearly not entering sidemount territory.

About 500' later Glenn called the dive on 1/3rds, so, regretfully, back we go. No hassles, no trouble, no other dive teams pass us. Just plain good fun.

4:30pm Dive ended with 70 mins bottom time. Gear packed and stowed -- nothing stolen, good! Nothing left in the cave -- great!

6:10pm Back to Playa del Carmen, dropping off the tanks en route. Filling up our ATOS we are surprised when it takes only 10 liters! Total petrol cost = 68 pesos ($6.20). Another great advantage of the economy cars, best gas mileage.

6:30pm Checking back into Hertz, no hassles, no headaches. Total cost is the agreed $340 pesos which I gladly sign for. This is my 3rd time renting from this Hertz office and it won't be my last! They even drop us off near the ferry via their own shuttle at no additional charge, though I customarily tip the driver for this service. Excellent timing for the 7pm ferry.

7:00pm Lucked out on both trips, we got Ultramar ferries (MX $110 mas, para return de Cozumel) which are nicer and newer than the other brand. It may just be aesthetics, but the ride on Ultramar just seems smoother, more pleasant.


Next planned trip is Monday, 29 Jan 2007. Possible destinations are either Sistema Nohoch na Chich or the upstream cave of Dos Ojos, although Sistema Ox Bel Ha is possible if we can find information on it by Monday.


NB: On the day we dove Gran Cenote, 25 Jan 2007, it was decided and published that Sistema Sac Aktun is now the Longest Cave System in Quintana Roo, Mexico! I am very proud to have been diving here on the day when this important record was established.