LOGBOOK FOR THE MEXICO TRIP (Aug 24 - Sept 7, 2001). Preliminaries. I left England in rather a rush, working right up to the day before I left and packing in a hurry the night before. Made a good job of the packing, all things considered, but arrived in Mexico already tired, which was not quite so smart. Dive 1 of trip (Dive 82 if it follows on from the rest of my e-logbook). ------ Catalogue of minor disasters at Chac Mool------------------------ All went well on the first dive on the Saturday afternoon - until I hit the waterline! Then, the fact that I had hardly dived since March a year ago (the previous trip to Mexico) really began to make itself felt in various equipment faults, and certain faults with the diver himself - my ears made it abundantly clear that they were only letting me dive as a special favour, and they forced me to take about 10-15 minutes to get down to the 40 foot depth of the main cave passage. Eustachian tubes way out of practice. Before diving I met the dive party of one Mike Madden, (as in Mike Madden's dive center, and also as in holder of the world record for line laid in a single dive when he, Dan Lins and Matt Mathes added 4584 feet to Sistema Nohoch Kiin) an amiable guy who however began by voicing the usual reservations about me being solo. I replied that some of my best dives on the previous trip had been solo, notably the "River run" circuit at Cenote Ponderosa, which I had soloed last time after the rest of Brent's party (even Erich) had left. "I'd surely rather be doing that than sitting on the bank, giving lectures on the perils of solo diving" said I, a little tartly. God bless his soul forever, Mike changed tack and we had a great little chat during which he told me exactly where to find the downstream guideline - I'd been upstream at Chac Mool before, but I never found the downstream guideline. That became my target when I entered the water, but it took a while to get there even though Mike's instructions were perfectly accurate. First, I flooded my primary light. This is a large 55W handheld torch made in the UK for wreck diving; I had downgraded it to 20W so the battery would last longer (circa 4.3 hours) in the caves. The airline refuses to carry any lead acid batteries in their planes, so I had bought a couple at the Aquanauts dive shop in Puerto Aventuras, for $50, - surely a better deal than renting a dive light for $10/day for 2 weeks. I found a home for them at the end of the trip, too. The fact that I flooded the light was my own fault, inspection revealed that the main O-ring was kinked out of its groove. Second, having fixed the primary light my ears really began to hurt as I made my way down to 40'. I really had to work to get them cleared - Valsalva manoevre done so hard I was dizzy at the end of it. Finally made it down there. Then, third, as I found the main line and attempted to deploy a primary reel, it immediately jammed solid. so that I had to return to the surface and fix it there. Once again my own fault, I hadn't checked that the line was wound correctly on its reel. It wasn't! It was a proper cat's cradle that took a few minutes to sort out. At some point in all this I noticed that one of my 3 first stage regulators had a small leak, no doubt an O ring was dry after a year in storage. During the next few days a few more leaks developed, 2 of my 3 high pressure hoses needed replacing, and the first stage reg. really needed a full service, second stage pressure much too high. I didn't have the tools with me to service it properly so got into the habit of switching that reg. off --- for emergency use only! I put the duff one on the left post of my doubles, putting the good ones on the right post and on the buddy bottle. Even on that first dive I knew Reg. 3 was suspect and put it on the left post. Oh and at some point while finding most of these faults, I did actually have a dive! I didn't go hugely far as (a) I didn't feel like it and (b) I had wasted air in the initial messing around. So I wandered 800 feet to where the line goes off to Cenote Emergency Air, and then came back - a very short dive for the shallow depths we get in Mexico. On returning to the surface I was pleased to note that my drysuit was perfectly non-leaky. My pleasure in this was however somewhat reduced when I tore one of the wrist seals to shreds getting out of it. Nearest replacement probably in Florida, people don't dive dry down here and do sometimes get cold as a result because of the long dive times, up to 2 hours even for the simple "tourist dives" I was doing. So I dived wet for the rest of the trip, which meant that I would be cold after a full 2 hour dive; so I sometimes limited dives to around 90 minutes or so. Dive 1 eventually consisted of 64 minutesround trip Cenote Chac mool to the jumpoff for Cenote Emergency Air, max depth 41', avg. temp 75F, dive profile (depths at 3 minute intervals as recorded by my Bridge) 0,26,40,41,39,40,38,39,32,39,29,35,39,38,40,40,41,39,40,30. Obviously, no deco needed. Solo! Interlude: Sunday in Tulum. After the first dive with all its problems I began to wonder if I was still cut out for all this cavediving lark, so many things had gone wrong, most of them my fault for lack of proper preparation. I took Sunday 26th off and bummed around in Tulum; but I also replaced a low pressure hose that was bulging as if fit to bust. The leaky high pressure hoses I didn't bother with on the grounds that you can't lose all that much air out of the tiny HP outlets - it's the low pressure outlets that really drain the tank down. By taking the day off I arrived much refreshed at the dive site on Manday. And I had a good dive. Dive 2 of trip (83). Monday 27th August. ---------------------Chac Mool Revisited.--------------------------- I decided to do the downstream Chac Mool for my first dive, and visit the upstream section (which I did before) on the second. But this time I expected to go a reasonable distance, more than the 800' to Cenote Emergency Air at any rate. To this end, I decided to count my buddy bottle in on the air supply calculations (this is also a way of persuading me not to leave it in the boot [=trunk] of the car!). In order that strict 100% redundancy still holds, I do this (when the buddy bottle is same size as one of the doubles) by breathing down to where the doubles are nearly half empty; one can then get out with the doubles only, or with the buddy bottle only. By now I knew Regulator 3 was dodgy [back in England I found its HP valve seat was astonishingly deformed - amazing it worked at all - faulty manufacturing of the seat maybe??] so it went on the left post which was switched off to avoid the gentle outflow of bubbles through the second stage. The second stage was clearly not at fault - worked OK with the other first stages. And the dive went as planned. I got quite a long way, though not the full 3500' to Cenote Mojara. I reckon I was about at the beginning of the Canyons section - I could see things were about to get deeper - when I turned on thirds. I had 1600 PSI at the turn and 200 PSI on exit in my doubles, the stage/buddy bottle untouched throughout; though "downstream", the current was negligible as far as air supply calcs were concerned. And I also exited with a smile on my face, because my confidence was returning, and with it the joy of being in the water again. In my element. Wonderful! So, a 116 minute non-deco dive (God Bless Mexico!) max depth 41', temp 75F; depth profile: 30,38,40,40,40,40,39,36,36,35,38,40,40,37, 36,34,33,38,36,38,37,34,35,37,38,40,41. Dive 3. Chac Mool. Monday 27th August. I entered from the main entrance to the cenote, not the side entrance which is where I went in before; somehow I couldn't get my bearings so I didn't find the upstream line. However I found several sidelines which I fooled around in until I started to feel cold.. 81 minutes, 52' max, 76F, depths 29,41,37,52,40,40,40,39,40,40,40,43,42,25,30,36,35,40,40,40,37,33,41, 41,39,41,39,10. Dive 4. Return to Sistema Tortuga. Tuesday 28th August. I decided to return to one of my favourite dives from the previous trip. I went down to the saltwater (deeper) section of Tortuga and had the first of 3 deco dives of the trip. I followed the main line quite a way back in there, some very impressive mudbanks and "drainage channels" like some of the passages at Devils Ear in Florida. 101 minutes of which deco 12@10. Max depth 81', 76F. Depths: (the initial messing around is because my watch strap fell apart in the cave entrance and I returned to the surface to fix it.) 8,0,0,6,0,0,10,13,12,17,30,39,50,76,78,79,79,79,78,81,78, 78,79,79,77,75,42,33,29,16,11,12,11,11. I think the name of the passage I was in may be the "black hills de la Tortuga" - at any rate, the mudbanks were convincingly black and hilly. Should mention that the small pond where Tortuga starts is soupy with algae in summer, but to my pleasant surprise the cave itself was completely, absolutely clear. I suppose I should have expected it, but you should see (or rather not see) the atrocious visibility in the basin. Dive 5. Sistema Vaca Ha. Wednesday 29th August. This one I had never done before. Like Tortuga (it's owned by the same nice old guy, and on the same property) it starts with a small pond, but Vaca Ha does not have an upper and a lower level like Tortuga, instead it winds on at a depth of around 68 feet. So, another deco dive. On this first dive at Vaca Ha I naturally followed the main line, which starts tied off to the foot of the ladder where you enter; I got to where the main line splits and starts narrowing down, before turning on thirds. 98 minutes (of which circa 20 deco), max 69', 75F. Depths 17,31,57,65,58,65,67,68,68,68,67,68,69,69,68,69,69,69,69, 68,66,62,64,40,31,11,10,10,10,10,10,10. Dive 6. Vaca Ha. Wednesday 29th August. The "exploding safety reel" dive. In this, my second dive of the day and 2nd at Vaca Ha, I resolved to follow up the first few jumpoffs from the main line, and see where they went. Now I had 2 reels with me, a primary and a safety. The primary was not used because the main line is tied to the entrance ladder of Vaca Ha, so I had a choice of primary or safety to use to make my jumps. I elected to use the safety (after all, if you're going to use a "safety" reel in a real emergency, probably it does no harm if it's as long as possible), and I was somewhat startled when it seemed to explode in my hands, 2 bits of it disappearing into the mud at the bottom of the cave. "What", says I into my second stage - "I COULD HAVE DONE WITHOUT THIS". What had happened was: most dive reels use circlips to hold the reel onto the spindle about which it turns. But this one (an English make) used a screw thread which (of course) had duly come undone, resulting in the explosion when I tried to use it. I retrieved the spindle and reel from the cave floor, and in defence of the British manufacturer it should be said that I then had it all reassembled in under a minute -- the reel would be very easy to free if it ever jammed, much easier than trying to fool with those tiny circlips on a Dive Rite standard. I followed the first three jump lines, none of which went hugely far, and exited with a general "good job well done" feeling about the day. I met Mike Madden at the surface again before the dive. Great explorer that he is, he was only doing short dives that day - I assume his buddies were much less experienced than he. 85 mins (circa 15 of deco), max 73', 75F, depths 31,56,65,70,73,67,66,62,67,62,71,70,71,70,71,60,58,56,50,58,57,58, 57,59,66,54,33,13,10,10,10,10,10 Dive 7. Sistema Aktun Koh. Thursday 30th August. Upstream. I asked Herve at Villas deRosa, what the best bit of Aktun Koh was. He replied, the Wonderland passage. And so I went upstream and took the first jump to the left, following the twists and turns of the passage until it eventually hit the gold line again. I had plenty of air left, so instead of exiting via the gold line, I followed it upstream to Cenote Bears Den, and then completed the Bears Den circuit just as I previously had with Brent, Jerry and Rick deVan. This would have violated air supply rules except that I already knew how much air I took to do half the Bear's Den circuit (1000 to 1100 PSI from my doubles). I arrived at the half way point with 1350 PSI in my doubles and 2700 in the single buddy bottle, so I completed the circuit, exiting with 250 PSI in the doubles and still, 2700 in the buddy bottle, which was untouched throughout. 116 mins, max 46', 74F, depths: 8,9,26,28,32,38,37,39,44,39,44,39,44,19,43,30,23,21,11,10, 7,22,37,33,43,42,40,30,34,37,39,29,30,22,21,25,27,31,31,29,10. Dive 8, Aktun Koh downstream. Thursday 30th August. I did some bits of the rather pretty, smaller scale passages of downstream A.K., that I had not previously done with Erich. To start with I went all the way to Cenote Overpass on the main line; coming back I went round the little loop they have in there (lines tied together a la European system) and also along a couple of jumps, one of which led to (yet) another small cenote, I guess that was Cenote Foxhole. A great feature of my day at A.K. was the free lunch, a party of tourists arrived at the sort of bar they've put up there since I was last in Mexico, just as I was resting between dives and I was warmly invited to munch out. I was also offered beer but declined in faour of coke with the obvious explanation that drunken divers don't last long. This dive was predominantly shallow, and my right ear was playing up by the end of it. I also had a system whereby I tied my carkeys to the drawstring of my shorts, so I could get at them without completely removing my wetsuit - the shorts stay on in the water. This system was brought into question when I nearly lost them by flinging them into a corner when I needed somewhat urgently to have a pee at the end of dive 2. But I decided to keep the system, in all other respects it works well. Near the same time my Coleman's Omni-Tool, which sits on my waist belt and functions as a divers knife OR pliers etc., also went flying. I must have ben really in a hurry! Rescued the tool as well. [N.B. Steve Gerrard's book is wrong when it says that downstream AK has a gold line. It's all white in the downstream area, though of course the upstream Bears Den bit is indeed gold line.] 101 mins, max 42', 74F. depths: 28,40,41,38,22,27,38,34,23,22,34,38,27,24,28,30,31,27, 26,31,38,39,21,35,31,38,31,38,27,37,42,42,38,8. Friday 31st August: GROUNDED due to ear infection. Stocked up on antibiotic eardrops, which you'd need a prescription for in the US/UK but buy over the counter in Mexico. Later took them home with me - they should last until I next get to Mexico! Saturday 1st September. GROUNDED due to vomiting/stomach upset. It's all happening on this trip! Sunday 2nd September. Dive 9. Sistema Minotauro, upstream. When I got to Cenote Minotauro (for me a new experience as was Vaca Ha), I noted the nice concrete steps going down to one end of the cenote basin, where there was an entrance into the water. I assumed wrongly that this was the main entrance. I found out my mistake when things became very narrow and silty, and the line ended at a jump onto a main line that (as I rightly assumed) came from the other end of the cenote basin. Wanting to do things right, I exited the way I had come and went and found the main line at the far end of the cenote. All lines are white, but I found one of 2 endpoints of the long circuit that is upstream Minotauro's main line. I did about 3/4 of the circuit before having to turn on thirds (even including my buddy bottle in the calculation). I was initially annoyed at myself for not completing the circuit - after all I went straight round the comparable length River Run circuit at Cenote Ponderosa - but afterwards I thought, wait a minute, 3/4 of the way round THAT circuit you have a cute little cenote (Cenote Zacil if I remember correctly) where you can recalculate thirds and so get right round. That doesn't happen in upstream Minotauro, though it's all fairly shallow. 99 minutes, max depth 47', temp 76 F, depths: 17,11,16,19,27,27,30,30,29,29,35,33,38,46,47,47,42, 42,41,40,43,42,46,47,44,34,36,31,27,27,14,17,13,6. Sunday 2nd September. Dive 10. Sistema Minotauro, downstream. Sidemount. ["What is sidemount, a sexual position?" - asked a young lady non-diver in Tulum, where I was discussing this dive with some friends at one of the dive shops] After dive 9 I identified the main line where I would have finished the circuit had I completed it, and noted that the main downstream line goes off from it at a T junction at the back of the cavern. Steve Gerrard's book points out that you realy need sidemounts to do the downstream Minotauro, so I got mine out. I followed the main line until it splits into 3, then followed the middle line until I was crawling along in mud with my drysuit brushing the ceiling, then toodled out feeling honour was satisfied. Downstream is very shallow, max 20' (!). Returning along the muddy passage was - hmm - interesting... it was nice to get back to the parts of the cave where I'd been able to keep my tummy out of the mud. Visibility jumps from less than zero to more than infinity, that's what it feels like anyway! 62 minutes, 74F, depths: 7,16,16,15,14,14,15,15,18,15,15,17,17,17,20,18,15,14. Monday 3rd September. Dive 11. Sistema Xunaan Ha. At Xunaan Na cenote they only charged me 30 pesos for admission, below the going rate of 50 for divers. A nice economy. Xunaan Ha is a good pool for snorkellers, 3 separate groups of them showed up while I was there. There's a guideline on the left wall of the cavern near the fallen tree, and another right at the back of the cavern. For the first dive of the day I followed the line on the left wall. This led to a nearby cenote, and then on for further than I cared to follow it - I slightly curtailed the dive so as to be warm at the end of it. 97 minutes, max depth 43', temp 75F. A fairly plain cave with the odd pretty room in there. Depths: 16,29,40,43,41,15,22,37,36,31,24,5,5,7,7,8,8,8,9,8, 13,32,7,5,13,31,38,42,41,37,23,22. Monday 3rd September. Dive 12. Sistema Xunaan Ha. For the second dive I took the line at the back of the cavern, and followed it and a couple of jumps for a considerable distance. If they've only surveyed 5000 feet of this cave, I've probably done about half of it, and I'm not surprised Gerrard concludes that there's more to be found. I'm hardly an expert but to me the cave says "I'm fairly big..". 85 minutes, max 30', 75F. Depths: 16,20,24,22,29,26,26,25,25,23,22,23,21,21,23, 22,25,25,22,21,23,25,20,24,25,30,26,26,27,25. Tuesday 4th September. Dive 13. Cenote Del Mar (Sistema Ox Bel Ha). A toe in the water here at Sistema Ox Bel Ha. Disquietingly, a Mexican joked with me while I was kitting up, "seen any more pipes like this one?", kicking a 3'' diameter pipe that might have been dumping sewage into the cenote, though I saw no evidence that this was in fact the case. Lacking the Spanish to interrogate him properly, I merely HOPE that they're not dumping sewage into the main entrance to the 3rd biggest cave system in the Riviera Maya. I did 18 minutes of diving and found a strap loose on my sidemounts (which I wore because Steve Gerrard talks about a "slight restriction" to get into the cave system. In fact they were unnecessary.) At that point I noticed I had inadvertently completed a small circuit and returned to the cenote where I fixed my gear. 22 mins, max 31', 76F; 22,24,22,27,29,31,26,17. Tuesday 4th September. Dive 14. Cenote Del Mar. What follows was recorded by my dive computer as a separate dive, but the only thing I did at the surface was dig out my Omni-Tool and tighten the strap on my left tank with the screwdriver attachment. Taking the main line this time I found a "feature" I've never seen in a cave before, namely multiple guidelines (3) running in parallel for hundreds of feet. One guideline was clearly the right one, being taut and decorated with line arrows; the other two were sloppy and undecorated, odd balls of string lying at one corner, yet another line crossing at a funny angle with no arrows to show what was going on. Don't do your lights-out air share in this cave! You'll end up wrapped like a turkey in 1,000,000 feet of useless guideline. The cave itself is quite fun, though undecorated this near the sea, with a definite I'm-a-big-system feel to it. 53 minutes, max 31', 76F, depths 17,26,31,30,27,25,23,25,23,24,23,23,245,23,26,30,31,25. Tuesday 4th September. Dive 15. Sistema Abejas. Having a little energy left after the previous short dives, I stuck my nose in at Cenote Tannic Trap (a little unfairly named, you could see at least 6 feet in the cenote basin). The system has several entrances, and the one I picked was clearly not the main one because the lines petered out after a few hundred feet. I got out my primary reel and explored a bit further (as usual it wasn't necessary to deploy it at the entrance); you could extend the lines in any direction, the limestone is that porous. The virgin passageway generated an "interesting" amount of percolation on the way back, though... 36 minutes, max 39', 77F (warm, especially in the cenote itself where Sun Trap seemed even more appropriate than Tannic Trap); depths 29,37,39,38,34,31,30,31,33,33,17,10,7. Dive 16. Sistema Dos Ojos. Traverse Cenote Dos Ojos -> Cenote Dos Palmas. Wednesday 5th September. This traverse is with the current, which is noticeable (though I thought it was down on last time I was there). Therefore I decided on a "rule of quarters" rather than a "rule of thirds" for this well known traverse. So I took 2 stage/buddy bottles rather than just one, so that my allowed air for penetration was exactly one stage bottle. At 2700 the stage was not quite full when I began (they have a habit of filling them to 3000 in brilliant Mexican sunlight so the pressure goes down a bit when you hit the cool water); it was down to 600 when I exited at Cenote Dos Palmas (hence I would have had to turn (at 750) if I hadn't had the extra stage). Dos Palmas was pleasantly empty after the touristy Dos Ojos, with a nice deckchair or two to sun oneself. 53 minutes, max 34', 75F; depths 21,26,28,29,29,28,22,30,32,30,32,30,34,34,23,24,23,21,20,17. Dive 16. Sistema Dos Ojos. Return trip Cenote Dos Palmas -> Cenote Dos Ojos. Wednesday 5th September. I left the nearly empty stage bottle at Dos Palmas to pick up later (NB it did not have a regulator attached because I have 3 regulators and on this dive, 4 posts to attach them to. Obviously I'd have had to change a reg. around to get at the last quarter of my air supply underwater on the outward journey). So I confronted the strength of the current with less drag than I'd have had with 2 stage bottles. I used 1700 PSI out of my doubles on return, i.e. 3400 PSI to compare with 2100 PSI used on the outward journey, a ratio of 34/21. Now if the ratio of gas breathed is going to be 34/21 on the way back, a rule of fourths is barely adequate - you really need a rule of fifths, which in fact I had kept to because of the 600 PSI left in the buddy tank at the end of dive 1. What should the rule be?? If you expect the ratio of air breathed to be up to 1.5, you can use a rule of quarters safely, because the 3/4 you will have left will be at least twice as much as you need to get out (which is 1.5 x 1/4 = 3/8 in the worst case). If you expect the ratio to be 1.5 to 2.0 you can safely use a rule of fifths - and that's really where I was, my ratio was 34/21 = 1.62. If you expect a ratio of 2.0 to 2.5 you need a rule of sixths, and so on. 71 minutes, max 34', 74F, depths: 14,19,21,22,23,23,22,24,27,34,30,26,32,30,26,28,28,27,28,28,28,25,18. Dive 18. Sistema Ponderosa: Cenote Chickin Ha. Thursday 6th Sept. Cenote Chickin Ha is the one at the upstream end of S. Ponderosa. Cenote X'Tabay drains into it through chnnels that are too small to admit a diver, so we get a separate Sistema X'Tabay. Chickin Ha has a splendid room about 200' in, sort of like a quarter scale model of Heaven's Gate at Nohoch Nah Chich. The rest of it is typical Ponderosa style passages, including a large chamber further in that would be the size of a banquet hall horizontally, but only about 4 or 5 feet high. The gap between two LARGE bedding planes, I guess. It was at this divesite that I met Geronimo and Flor de Maria, two of the original explorers of S. Minotauro (they appear on p. 129 of Gerrard's book: Flor de Maria's are the feminine features behind the dive mask of the lead diver, Geronimo is following). They were showing a less experienced diver round the cavern zones. 80 minutes, max 43', 75F, depths: 31,43,41,35,37,37,36,32,27,20,15,23,24,29,29,28,23, 15,28,30,37,39,38,39,43,42,31. Dive 19. Cenote X'Tabay. Thursday 6th Sept. Apparently this one goes for about 2.5 hours of diving; Geronimo gave me instructions on finding the main line, and I gave it a modest 77 minutes. Mostly saltwater passages; the odd decorated room. Max 43'; 74F. Depths 10,0,30,38,38,35,37,27,30,40,41,42,41,41,43,42,42,42,42,41,31,27,38,40,39,27. (the zero is because I managed to explode the safety reel again). Quite a good cavern dive - I could see why G. and Flor de Maria picked it to show to their less experienced friend. Last dive of trip! Ah, well.