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By Alberto Nava
Header photo by James Babor.
After doing all my closed circuit rebreather (CCR) critical control checks, i.e., “CHAOS,” I jumped into the water to find myself in warm, cobalt blue water. We descended to 6 m/20 ft, did a quick bubble check, and started our descent. My automatic diluent valve (ADV) delivered a wonderful trimix 15/60 (15% O2, 60% helium) mix as I dropped down the wall and leveled off at about 60 m/197 ft. A large black grouper came to greet us, and we quickly reached the 65 m/213 ft overhang on the wall—the old coastline from the previous ice age. We followed the grouper inside the overhang and reached 80 m/263 ft. We found two large lionfish resting on a sizeable white sponge, and large strands of black corals and colorful gorgonian were all around. We turned our bodies into the current and began our 180-minute drift dive along the incredible walls of Cozumel. We were in heaven!
As we drifted along enjoying this incredible dive, my mind drifted back 20 years ago,
when I used to dive the Caribbean Sea in my home country of Venezuela. At that time, I had just become a PADI divemaster and used to take people on warm-water adventures in Venezuela’s national marine park, Los Roques Archipelago, near the island of Bonaire. As a divemaster, we limited our dives to 30 m/100 ft and closely followed the no-decompression limits. The tools of those times were single aluminum 80 (AL80) tanks, a warm-water wetsuit or no wetsuit at all on some dives, and the famous multi-level diving PADI wheeI.
In my 20-year evolution as a diver, I’m so thankful to have found the Global Underwater Explorers (GUE) organization and its amazing mentors, which made my 180-minute dive to 70 m/230 ft seem as simple as the old single tank diving of my past. Is this for real? Can Caribbean diving be even more incredible with GUE tools? Please allow me to take you on my rediscovery of the Caribbean during the last three years, with the hope that you will also enjoy the incredible natural resource we have at our disposal.
In 1998, as technical diving was just getting started, I moved to California after spending a few years attending school in Sydney, Australia. My time in Oz had left me a bit frustrated, having experienced what I now perceive as dangerous deep air dives in the Sydney Harbor as well as in the caves of Mount Gambier, near Melbourne. I arrived in California wanting to learn to use alternative breathing gases for going deeper.
I experienced improvements on the diving procedures and gases while training with West Coast technical diving pioneer Wings Stock from Santa Cruz, where we used to breathe trimix 20/20 (20% O2, 20% helium) at 67 m/220 ft. But, it was really not until I took my GUE Tech 1 class in 2001 that deep diving came to a new light. Helium was such a wonderful gas to put in our tanks, and the more the better. For me, doing a 46 m/150 ft dive with 35% helium removed most of the ambiguities of deep diving, reduced the risk, and made deep diving a much more enjoyable experience.
Living in Monterey, I was able to explore and document many of our deep water pinnacles, including those at Point Lobos Marine Reserve, Big Sur Banks, and others.
Unfortunately, I quickly forgot all about the Caribbean and settled in as a cold-water California diver. During that time I also started going to Mexico to dive the amazing caves of the Yucatan Peninsula.
Fortunately, I got better at cave diving, got into exploration, and was lucky to discover the Hoyo Negro Pit and an amazing assembly of animal and human remains from the Late Pleistocene. From 2007 to 2014, Hoyo Negro, underwater archaeology, and scientific diving were at the center of my diving world. As time went by, my distant past as a Caribbean diver faded more and more from my diving horizons.
The Return to the Caribbean
In 2014, I reluctantly agreed to a warm-water diving vacation with my girlfriend. Cozumel was close to the caves, so I figured I could do my cave diving project, then spend a few days of diving Cozumel in order to make everybody happy. However, as soon as I jumped into the water, I recognized the warm, blue water surrounding my body and realized I had been there before; in fact, it was imprinted in my mind.
I was quickly able to find all the little creatures inhabiting the reef, including seahorses, green moray eels, and arrow crabs, and the larger creatures as well: barracudas, eagle rays, and nurse sharks. I felt about 20 years younger, having returned to my natural environment. On the second day of diving, after the divemaster gave us a check out, we ventured to the Cozumel wall. We quickly dropped to 30 m/100 ft, and I could see the wall going down, probably to 60 m/197 ft. I immediately wanted to go deeper on the wall and explore! However, considering my minimum gas reserves, equivalent narcotic depth (END), and maximum operating depth (I was diving nitrox 32), I realized that I needed the right tools.
By the end of the trip I was convinced I needed to come back to Cozumel with GUE tools. At a minimum, we needed to ditch the single tanks for doubles, or better yet a rebreather, and find a way to get helium, Softnolime, and a reliable boat operator willing to conduct some fun tech dives.
I got back home and started talking to Cozumel veterans about how to get the equipment and support I would need for deeper diving. The most common answer I got was, “People in Cozumel don’t like deep diving.” There had been too many accidents, so they didn’t want to take people deep on the reef. Furthermore, my inquiries with dive operators were not successful; the best answer I got was that some shops had larger steel tanks.
I eventually found a dive operator who was willing to conduct deep diving and had a great boat and crew. Unfortunately, the owner of the shop had had problems with GUE divers from the early “Doing It Right” era of the ‘90s, and thus was not very welcoming to me as a GUE diver or instructor. It took a lot of energy to convince him that I was a nice person, and that I was not going to call him a “stroke” or require him to wear all Halcyon dive gear. After numerous meetings, dinners, and some mescal, I finally had access to a good boat, an experienced crew, and the all-important helium.
Fun Diving GUE Style
Over the last three years, my friends and I have conducted numerous fun dives in Cozumel and held some simple classes. Here is a description of what’s possible starting with the simplest diving and going to the more complex.
- Recreational diving with doubles: For me, this is entry-level Caribbean diving. You get two sets of doubles filled with 32% and conduct two dives in a day. Each dive is a multiple-level “no-stop” dive on the reef with a max operating depth (MOD) of 30 m/100 ft. Total run times are around 75 min, and typical dives have three levels with 20 min at 30 m/100 ft, followed by 20 min at 18 m/60 ft, and another 20 min at 10 m/30 ft. Divers then use their remaining gas until their runtime is in the 75 min range. Our boat operator allows for two 75 min dives when doing recreational dives. This allows for good time at depth followed by fun diving along the wall. All that’s needed to participate in this type of diving is GUE fundamentals and a doubles primer.
- Tech 1 dives: For GUE Tech 1 divers, the equipment of choice is a set of AL80s typically filled with trimix 18/45, and a nitrox 50 (50% O2) AL80 stage for decompression. This is the perfect combination of gear to venture on the wall with a max operating depth of 52 m/170 ft (Note that GUE standards set a maximum pO2 of 1.2 atm during the working phase of the dive, and 1.6 atm during decompression), and again a run time of 75 to 85 min. Divers can multi-level their dives into two segments with 15 min spent at 52 m/170 ft and another 15 minutes at 40 m/130 ft, followed by a nice relaxing deco drifting along the shallow reef. In order to increase the fun during deco—we call it “Fun Deco”— we make the stops longer and spend more time on the reef. A typical decompression profile might be five minutes starting at 21 m/70 feet on nitrox 50, five at 18 m/60 ft, five at 15 m /50 ft, five at 12 m/40 ft, five at 9 m/30 ft, and 10 min at 26 m/20 ft. It’s easy and FUN! AL80s and wetsuits are also an ideal combination; no need for a drysuit there. During the summer months the air temperature is around 90 degrees Fahrenheit, and the water might be as warm as 87 degrees Fahrenheit.
- Tech 2 dives: As people want to dive deeper on the walls, GUE Tech 2 divers get either a bottom stage to increase their time at depth, or we also have low pressure LP85 tanks available for them. They typically use both nitrox 50 and O2 for decompression. The best part of the reef is the old coastline in the 60-80 m/197-262 ft range. In order to make their gas last longer, T2 divers can also multiple-level their dive, dividing their bottom time between maximum depth and time at 45 m/148 ft. In Cozumel, there is plenty to see at maximum depth. Similar to T1 divers, decompression is done on the reef and plenty of time is spent in the 12-9 m/40-30 ft range while still on the reef, until heading out to 6 m/20 ft for a bit of O2 deco. While at 6 m/20 ft, you can still enjoy diving as you look at a school of barracudas, trevally jacks, and the occasional shark. Watching turtles is one of the treats during decompression.
- CCR dives: The ultimate Cozumel tech dives are conducted by rebreather divers. The operator allows us to drift for up to 180 minutes, but in exchange for the long bottom time, we only conduct one dive. It’s not uncommon to have bottom times in the range of 60 minutes in the 70-80 m/230-262 ft range. These profiles require longer deco but one does so drifting along the Cozumel reefs.
The CCR allows for more flexible decompression and increases the enjoyable part of the dives. It’s not uncommon to extend the stops in the 37-21 m/120-70 ft range diving inside a coral head. We often make our stops for 20 minutes every 3 m/10 ft on our way to the surface, which allows us to stay on the reef for most of the dive. Our 6 m/20 ft stop is not much longer than the previous stop, which is a big change for people accustomed to long 6 m/20 ft stop hangs.
All in all, diving Cozumel with the appropriate tools provides for an incredible experience and allows you to practice your skills in a wonderful and warm environment. I plan to organize several trips to Cozumel in 2020. I hope you’ll be able to make it.
Beto will be running a number of ‘tech” trips to Cozumel in 2020. If you are interested please contact him at: firstname.lastname@example.org
Alberto “Beto” Nava is a Venezuelan-American engineer, diver, dive instructor, and explorer based in California. He has over 18 years of diving experience and has completed over 500 cave dives. His longest cave exploration penetration dive has been 4.7 km/15,500 ft. He and his group of fellow divers particularly enjoy exploring the cenotes in the Yucatan region of Mexico.
It was on one of these excursions that he and his colleagues discovered Hoyo Negro, or “Black Hole.” The bottom of Hoyo Negro contains bones of several Ice-Age megafauna and bones of a young girl who lived 13,000 years ago. They named her Naia. This discovery started one of the most important studies of the first Americans in recent history. From 2011 to 2015, Nava was a National Geographic Explorers Grant recipient. He used the grant to continue diving and photographing Hoyo Negro. His photography is now being used in the innovative labs of the Cultural Heritage Engineering Initiative at the Qualcomm Institute at the University of California, San Diego, to create a unique 3-D experience of Hoyo Negro for those who cannot do the difficult dive and would like to experience and study the space.
Nava has also published several papers on diving, underwater mapping, and the discovery of Hoyo Negro. He holds bachelor’s and master’s degrees in computer science from the Simon Bolivar National University in Venezuela and has worked as an engineer for over twenty years.
A Journey Into the Unknown
Sailor, diver, and professional software implementation consultant turned adventure blogger Michael Chahley shares his quest to discover the unknowns of our world by stepping out of his comfort zone. Are you ready to take the plunge?
By Michael Chahley
The engine roars to life, launching me out of a deep slumber and into reality. “That’s not good,” I think out loud. Rocking in my bunk inside the sailboat, I realize the wind is still driving us against the ocean swell. We do not need to be using the engine right now, so why is it on? Bracing myself, I climb into the cockpit as Paul, the captain, swings us over hard to starboard while staring wide-eyed ahead into the darkness. We are on a collision course with an Indonesian fishing boat shrouded in darkness, and it’s close enough to violate the ceiling of a safety stop. Rubbing the sleep out of my eyes, I count a handful of men staring back at us as they also take evasive action. One of them is standing at the railing brushing his teeth while we run parallel alongside one another for a moment.
Luckily for us we didn’t collide. I went back to sleep with another adventure to share. If you were to meet me today, working a full-time job in Canada alongside Lake Ontario as it freezes, it would not be obvious I spent two of the past four years traveling. Balancing a life of adventure with one of responsibility, I feel fortunate to have explored some very remote places in our world–both above and below the water. But before I was able to explore the Pacific Ocean, I first had to navigate a personal path of conflicting identities in order to find the confidence to jump into the unknown.
For my entire life, I have been more comfortable in the water than on land. My childhood memories consist of watching my parents dive under the water for hours at a time and swim in the currents of the Thousand Islands in the Great Lakes region of North America. I followed the predictable path of our society. I worked hard, achieved an engineering degree, and secured a job. Fortunately, I was able to continue exploring the outdoors with this busy life. Long weekends were spent diving in the Great Lakes or camping in the back-country. I was comfortable enough; however, there was no real satisfaction in my life. As the years ticked by, the gap between my reality and dream world grew. Something had to change, but I did not know where to find the catalyst.
Like any other armchair traveler, I idolized the explorers from the Age of Discovery. Adventure books weighed down my bookshelf while travel documentaries glowed on the TV screen in my room at night. I understood what made me happy, but I was unsure of what I stood for and believed in. I was living a life in conflict with the trajectory I wanted to be on, but I had no idea of how to become an ‘explorer’ who lived a life in pursuit of the unknown. While commuting to work each day in a crowded subway, I daydreamed of sailing the oceans and exploring the underwater world. As I grew increasingly more frustrated, one day I unloaded my concerns on a friend. They had the nerve to say I was ‘living in a dream world’ and needed to focus more on my real life. This hurt to hear at first, but then it dawned on me! If dreaming was a part of my life, then why couldn’t I make it a reality, too? This was the catalyst I needed.
I finally understood that even though others might see my dreams as frivolous, it was okay for me to follow a path that was meaningful for me. Like a weight lifted from my shoulders, I discovered it was okay to be uncomfortable with the status quo. With this in mind, I quit my job, packed a bag, and with no concrete plans, bought a one-way ticket to go halfway around the world.
One-Way Ticket To Ride
I found myself flying to the Marshall Islands with a one-way ticket to meet someone I had only communicated with over email. The customs officer did not find it amusing, but after some tactful negotiation, I was let into the country and even offered a free ride to the marina. It was 2016, and I was on my way to meet Tom, the captain of a 53-foot, steel-hull ketch named Karaka. Tom invited me to join his crew and help them sail across the Pacific. Even though blue-water sailing was new to me, for him it was a lifestyle. He was nearing the end of a 12-year circumnavigation after saving Karaka from a scrapyard in Hong Kong. Along the way, he would have crew join him as a co-operative, which is how I ended up spending eight months on his boat exploring the Marshall Islands, Micronesia, and Papua New Guinea.
When not visiting uninhabited atolls, the outer communities we visited were so isolated that we were asked to help out by delivering fuel, cooking oil, and mail. During this trip, our daily routine consisted of free diving on pristine coral reefs, gathering coconuts, and sharing meals with some of the friendliest people in the world. From spearfishing with the local fishermen, exploring the shipwrecks and ruins of World War II, and partaking in long walks on the beach or up a volcano, it was a new adventure every day. As a shipwreck enthusiast, I am incredibly grateful to have had an opportunity to free dive to within sight of the HIJMS Nagato in the lagoon of Bikini Atoll and to dive on Japanese Zeros in waters of Rabaul. Never in my wildest dreams would I have imagined myself exploring these regions of the world; reality had transcended my childhood fantasies.
Just like diving is for many of us, once I started traveling, the passion grew and is now a core part of my identity. Flash-forward to earlier this year, and I am back in the capital of Papua New Guinea helping Paul and his partner repair their 34-foot sloop named Amanda-Trabanthea for a journey out of the country and into Indonesia. Adventurers themselves, they had just returned to their boat after sailing through the Northwest Passage. Over three months we managed to visit some of the most hospitable and isolated regions of Papua New Guinea and Eastern Indonesia. I was lucky enough to go diving in Port Moresby, the Banda Islands, Wakatobi, Komodo, Lombok, and Bali. By the time we survived the near-collision with a fishing boat, I had come to expect the unexpected and cherish the exciting moments in life.
Explore The Unknown
Diving and sailing share a lot of similarities. Both are perfect for getting off the well-beaten track to explore places of our world few have ever seen. We must be confident in our abilities and have the appropriate training to safely handle the unexpected. A strong technical understanding of the physics and equipment required to operate safely is very important. Meticulous planning is essential for completing long passages and technical dives. But most importantly, it is the adventure from exploring new places that makes it so fun and gives us reasons to continue doing this. I strongly believe that communities such as GUE play a pivotal role in society by encouraging and promoting exploration within the individual. With time, I will combine my passion for both diving and sailing to help discover some of the most remote and beautiful corners of our world. If you have never sailed before, I highly recommend it.
I am back in Toronto where this journey began. I’m working full-time; however, this time with a much more solid understanding of myself and as well as a greater appreciation of the world we share. Only by stepping outside of my comfort zone to explore our world I was able to overcome the uncertainty that kept me from living an authentic life. Author Dale Dauten put it succinctly, “Success is an act of exploration. That means the first thing you have to find is the unknown. Learning is searching; anything else is just waiting.’’
During my travels, I realized that we cannot let others define us. We must reach beyond personal boundaries, take a risk, and venture into the unknown. In doing so, we become explorers in our own reality, which is the only reality that matters. So, rather than daydream about future adventures, we need to believe we can incorporate those dreams into our lives. All we have to do is to dare to take that first step into the unknown.
Michael Chahley is a professional software implementation consultant and an industrial engineering graduate from the University of Toronto. A finalist for GUE’s 2019 NextGEN Scholarship, he is a passionate diver, photographer, outdoor enthusiast, and an experienced traveller. Founder of the online blog Nothing Unknown.com, Michael is on a quest to discover the unknowns of our world and share them with you. He lives in Toronto, Canada, and can be reached at @NUDiscover on social media or his email email@example.com.
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