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Diveguide Dominican Republic

The growing popularity of scuba diving means that many vacationers are certified divers looking for good diving spots, and many novices are curious to learn what is going on underneath the sea. While the Dominican Republic is a great place to begin diving, it is also a haven for serious aficionados. The country's undersea world has excellent reef diving, good visibility, warm waters, wrecks, caverns and marine life offering a wealth of diving experiences around the island.

In the North Coast region of Puerto Plata, visitors staying in resorts from Costambar to Cabarete head to Sosúa for diving. It is an excellent area for taking classes and satisfying Open Water Certification course requirements. There are shallow reefs where beginners can sit on the sand underwater and watch the tropical fish swim by. Sosúa also has great advanced dives, too, especially in the waters near the international airport, ten minutes away. The main diving spots there are Las Palmitas, the Airport Wall, Five Rocks, with plenty of coral, and La Pirámide, a series of interconnecting tunnels. The best months for diving in the North are June to September when the water is at its calmest and visibility is at its best. East of Sosua, about 3 kms. from Cabarete are more sites for advanced divers.

An hour from Sosúa in Río San Juan, visitors staying at Caribbean Village Playa Grande can dive with the Grí Grí Dive School. The surrounding waters offer good beginning and advanced dive sites with abundant tropical fish and marine life. It is possible to see dolphins, whales (from January to March), barracudas, groupers up to 1-1/2 meters long and many colorful reef fish.

In nearby Cabrera, advanced divers will enjoy fresh-water cave-diving through wide tunnels. The site has a beautiful inland lake, where the light effects are amazing with the 10-meter wall and the underwater trees reflected. Further along the North coast is Las Terrenas which has a dive site called "The Whales," where one can dive in holes and view lobsters, groupers and coral formations. El Portillo Beach Resort offers special scuba diving packages with your own or with rented equipment. A full range of instruction is also available through the resort for open water diver certification to dive master.

In the northeastern peninsula of Samaná, guests staying at the area's hotels such as Gran Bahía, Hotel Cayacoa or Hotel Cayo Levantado. Here, off the Las Galeras beach is the Cabrón, an advanced dive site from 5 meters to 54 meters down with plentiful rock and coral formations, tons of fish, and a wall.

Heading west of Sosúa along the North coast are wrecks to explore off the shores of Cofresí and Montecristi. Major salvage operations are underway in the waters off the province of Montecristi. One particularly interesting dive trip is to Punta Rucia near Montecristi. There, an atoll called Cayo Arena (Sand Island), has incredible coral diving. Cayo Arena is sometimes covered completely by the ocean, and at other times is extremely visible for exploring.

Qualified divers can join the search and salvage team of North Caribbean Research and join professionals to look for sunken ships using state of the art search and salvage equipment. This company has a contract with the Dominican government to uncover and remove artifacts that the sea has held for centuries. There are over 20 shipwrecks to choose from, including the historic 1563 fleet.

This fleet was made up by the Spanish ships Santa Catalina, San Jorge and Santa María de Guadalupe, that left South America, with a stop in Honduras. En route back to Spain in 1563, they were caught in a storm, and crashed into a reef in the Montecristi area. Only the Santa María was salvaged. The other two ships drifted off the reef and went down in deep water (60-90 ft.). Lost was a cargo of jewels, gold, and more than 300,000 silver coins.

In the South coast of the Dominican Republic, there are two well known dive shops in the capital city of Santo Domingo that plan excursions, and rent or sell equipment. The best area for enjoyment of reef and wreck dives, night dives and fresh water cave diving near Santo Domingo is La Caleta National Underwater Park. At La Caleta, one can choose either shallow or deep water diving. During the months of November to January, the water on this side of the island is at its calmest, increasing visibility to its maximum level.

Here, you can discover the Hickory wreck, an iron ship used many years ago to explore Spanish galleon wreck treasures. A second more recent wreck, at a depth of 100 feet, is only a few minutes away by boat from the Hickory. The coral formations at this depth are a carpet of color, a tapestry of textures creating a profound sense of wonder at the delicate balance in this ecosystem. This underwater park can be reached in about 17 minutes by fast boat from Boca Chica, or about 25 minutes by slow boat from the public park on Las Americas highway. The Don Juan Beach Resort in Boca Chica is located near La Caleta and has its own PADI-certified diving school which offers diving trips to the area and across the island.

Another good diving spot for experienced divers is Catalina Island, where the "wall" attracts not only vacationers from the nearby La Romana resorts but also divers traveling from the North coast. The site is 20 minutes by boat from a dock in La Romana. This is probably one of the few places to see very large fish, such as grouper. Most of the big species around the island's popular coral reefs have been depleted by intensive spear fishing. Catalina's shallower dive of about 25-30 feet off the island is simply beautiful. An abundance of purple sea fans, orange, brown and gray gardens, and a variety of multi-colored, fluorescent fish surround divers as they wander about. There is excellent visibility of 90-100 feet and good light refraction.

Near to La Romana is Bayahibe where large schools of fish are accustomed to bread feedings from local divers. Just waving a white glove will produce a flurry of activity. This practice is being discouraged by ecologically-minded people as it reduces the survival instincts of the fish, and disrupts the food chain.

A popular area for diving in the Southeast of the country is Saona Island, which can only be reached by boat from La Romana. The island is a protected sanctuary within the National Park of the East, and there is abundant wildlife and marine life, such as turtles, whales, sharks and a good chance of seeing big fish.

Punta Cana located on the East coast of the island, with its own international airport, features the longest coral reef in the whole island - of about 30 kilometers long. There, the Punta Cana Dive Center operates with its base at the Punta Cana Beach Resort. The center is a member of the PADI International Resort Association. It offers PADI certification courses for all levels including rescue diver and dive master which can be completed in 6 days. The Dive Center provides all material and equipment for the certificate process.

Beginners to advanced and professionals may enjoy visits to reef caverns and wrecks, or participate in night dives and excursions to Catalina and Saona Islands. The Punta Cana Group is ecology-oriented, and maintains an active program for the preservation of the flora and fauna of the area.

An isolated place along the southwest shore, Los Bajos in Bahía de Ocoa (Ocoa Bay), has been reported to have large fish populations. Only a two-hour drive from Santo Domingo, the bay is a popular weekend resort for many people who live and work in the capital, but have beach houses along the quiet, gray-sand shores of Palmar de Ocoa. Further to the West is Barahona, a new area now being developed for ecotourism,which should be on the list of divers seeking unexplored and seldom-visited sites.

Many beach resorts around the country offer diving packages and guided excursions. There you can obtain your certification in an intensive course over a few days. Basic and advance training are available.

 

Source: http://www.diveguide.com



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Scuba Diving Classes (PADI, NAUI, SSI) PDF Print E-mail
Written by Andreas Ackerl   
Thursday, 29 July 2010 10:59

These are three of the world's best and largest diving training organizations that offer scuba diving courses and classes.

PADI or Professional Association of Diving Instructors (www.padi.com):

In the recreational diving membership organizations, PADI is the world’s largest, with offices in Australia, Canada, Switzerland, Japan, Sweden, the United Kingdom, New Zealand and the United States. PADI started in 1967 and the main corporate headquarters is located in California, and is known as PADI Worldwide.

PADI offers Open Water Diver course, the most widely accepted and esteemed diving certification in the world. One of the popular entry level trainings PADI offers is the Discover Scuba Diving program, accessible at any PADI Dive Center or Resort. Basic concepts and scuba skills are taught here under the supervision of PADI Professionals in pool or pool-like conditions. Though minimum age requirement is 10 years old, younger kids can also attend the “junior” courses.

The entry level training emphasizes on practical safety issues instead of theoretical concepts such as the physics and chemistry of diving. The Discover Scuba Diving program is followed by the PADI Specialty Diver and PADI Rescue Diver programs for people who want to continue. These include advanced training and additional skills specific to personal interests. After each course is completed, a certificate is issued which is widely accepted throughout the world as proof of proficiency. PADI issues almost 946,000 certifications each year.

NAUI or National Association of Underwater Instructors (www.naui.com):

NAUI Worldwide was established in 1959 as a non-profit diving membership association, and organized solely to support and promote Dive Safety through education, which has now become the second largest diver training organization. Their training programs include Skin Diver through Instructor Course Director, with several number of specialty courses including Search and Recovery Diver, Scuba Rescue Diver, Nitrox and technical diving , to name a few.

NAUI also includes Technical courses, Leadership courses and Recreational courses. Recreational courses include Skindiver, SCUBA Diver, Experienced SCUBA Diver and Advanced SCUBA Diver. NAUI’s certification class is for people above 8 year-olds and you don’t have to be an accomplished swimmer. For younger kids, there is also a “Snorkeling for Kids of All Ages” non-certification class.

SSI or Scuba Schools International (www.divessi.com):

SSI is also a worldwide diving training organization that specializes in business support for dive businesses that was established in 1970. It is, in fact, the largest school-based training agency in the world with various regional centers, and its certification is widely accepted throughout the world. They have a SSI Facility Search feature on their website if you need to get region-specific information.

The beginner programs offered by SSI include Scuba Ranger, Try Scuba, Passport Diver, Open Water Diver, Snorkeling, and Scuba Skills Update. In order to reach SSI’s highest recognition level in diving - the Platinum Pro5000 Diver award, you have to go through a number of intermediary such as Stress and Rescue Diver, Specialty courses, Continuing Education Ratings, and advanced programs such as Dive Leader Education System, including Dive Control Specialist and Open Water Instructor.

Source: http://www.scubadivingplanet.com/articles/templates/general.asp?articleid=31&zoneid=1

 
Online Scuba Diving Lessons PDF Print E-mail
Written by Andreas Ackerl   
Wednesday, 28 July 2010 10:44

These are some of the popular websites and agencies in the United States that offer academic online training, lessons and certifications for scuba diving.

SDI's on-line scuba diving learning program: (www.scubadiver.cc/onlinetraining.htm)

Dayo Scuba, based in Orlando, offers the SDI (Scuba Diving International)’s online training program concentrating on the academic part of scuba diving lessons, for $84.95. This program is aided by graphic illustrations and animation of key concepts by using motion pictures, animated pictures, and diagrams.

The course can be taken according to one’s own pace and schedule, and any lessons can be repeated. There are also periodic quizzes related to important concepts before progressing to new material and lessons. The academic is followed b the in-water training dives which costs $234.05. After completion of both courses, you’ll receive an Open Water Diver certification from Scuba Diving International.

Dayo Scuba also offers free software for better understanding of buoyancy, and forms and drivers that may be essential, on this webpage.

Force-e: (www.force-e.com/instruction/sdi/sdi_online_scuba_training.shtml)

Force-e is a diving center based in South Florida. Approved and authorized by Scuba Diving International, the Force-E online scuba diving academic instruction offers an online training program, which must be completed before continuing with the pool and open water dives, and scuba diving certification.

The online course includes subjects such as underwater environment, dealing with the effects of pressure, planning and monitoring dives, and important considerations when selecting scuba diving equipment. The online dive training also offers a text book after completion available in order to review the information anywhere. The Academic Online Dive Training is subsequently followed by Confined Water Dive Training and Open Water Dive Training.

You can call their toll free number for $ 84.95 to receive the sign-up code which you need to enter in the website. Otherwise, you can simply register online with a credit card.

Scuba-training.net: (www.scuba-training.net)

Scuba-training.net, based in Vero Beach, Florida, offers several online scuba learning courses including open water scuba and specialty courses, like dry suit diving, surface supplied air diving, and many others. They also have advanced training and certification including Nitrox and Rebreather Diver training. You have to pay $84.95 for the online academic portion of your Basic Scuba class while specialty classes will cost you $49.95.

Scuba-training.net eliminates the need to repetitive and time-consuming classroom sessions since the system adopted by the course is designed to let student work with materials that are specifically personalized, which can be learned according to one’s own pace and schedule. Dive instructors and shops also have full online access to all of the students' records and study information for review.

The organization offers CMAS (The World Underwater Federation), PSA (Professional Scuba Association), and SDI (Scuba Diving International) certifications.

Onlinescubalessons.com: (www.onlinescubalessons.com)

The website offers an Interactive Online Scuba Dive Lessons and Training Correspondence Course mainly concentrates on Physics and Physiology of Scuba Diving. The $49.95 course includes 5 modules, final exam, and Academic Certificate.

The modules include subjects such as Equipment, Underwater Sciences, Physiology, Diving Environment, and Planning and Decompression Sickness. Before proceeding to the next section, you need to have a 100% score on each quiz that will be given to after completing each section.

After passing the final examination, you can take your certificate to any instructor or agency and continue with the pool and open water dives trainings.

Source: http://www.scubadivingplanet.com/articles/templates/general.asp?articleid=35&zoneid=1

 
Go Scuba Diving In Maui PDF Print E-mail
Written by Andreas Ackerl   
Monday, 26 July 2010 11:13

Do you want to see a side of Maui like never before? Check out the beautiful island of Maui from a different view- underwater! There are many places in Maui where you can go scuba diving even if you have never been before. You can go on a guided tour, learn from an instructor or rent equipment if you don’t have your own. Below is more information about snorkeling and scuba diving in Maui.

Diving Trips

There are many different diving trips for you to choose from if you are staying in Maui. Many places offer small group SCUBA trips to at least two different destinations on each day of the week. Set out with other divers on a fully-equipped dive boat and enjoy comfortable seating and amenities (such as a bathroom) while you travel to your dive location.

There are knowledgeable crew members and diving instructors that can help you no matter what your level of experience and most dives are very affordable. If you are concerned with price, you might also look into package deals to save you money or go with a group.

There are also many specialty diving opportunities such as diving in caves or caverns. There are special excursions you can take with a professional tour guide to show you sights you probably never dreamed of before.

If you are a novice diver or if you are in a party with snorkelers, then you might want to take a different boat trip or tank dive trip. You will have to contact facilities that offer these to find out all the details. There are also many introductory dives and diving courses for you if you are new to the underwater world.

Snorkeling Trips

In addition to scuba diving, you might want to try snorkeling. There are many places that let you view gorgeous coral reefs and much more as well as the many exotic underwater living creatures of the Hawaiian Islands. Set out on a boat with many other snorkelers whether it’s your first time or you’ve been doing it forever. Head out to a nice snorkeling location such as a coral reef and friendly, knowledgeable crew will help you even if you have never done this before. There are “boogie boards” available to help you while moving through the water.

Even if you have been snorkeling before, you have likely never seen it like it is in Maui so it is well worth the time to go for at least one day and check it out. Snorkeling usually costs around $50 a day per person but you will have to call actual facilities since prices are subject to change. There are also group deals and discounts that you may be eligible for as well if you call and check into it.

Diving Courses

If you don’t know how to dive, you might want to look into getting some instructions first before you set out to go on a dive with people that know what they are doing. There are also many places that offer diving courses for those of you that may not have even been diving before. You can take classes on all the details of diving as well as go out on a boat with an instructor that will show you exactly how to do everything properly and safely.

If you are looking to find out exact pricing and diving schedules for different resorts and facilities, you will have to call them to find out all of the details. Equipment rentals can vary in pricing according to exactly what you need and what company you go through so you have to call to find out for sure. There are some places in Maui that offer trips and equipment that have their information available online and this may make it easier for you to plan ahead for your trip and find which location you want to use.

If you are going to be in Maui for vacation, you really need to take at least one day to go scuba diving or snorkeling and see the amazing underwater world in person for yourself. You might even want to take along an underwater camera to remember your adventure.

You can check into pricing, dive days and times as well as what certifications they have and what comes in their deals to help choose the one that suits your needs the best.

Source: http://www.scubadivingplanet.com/articles/templates/general.asp?articleid=28&zoneid=1

 
Learn Spanish and Scuba Dive PDF Print E-mail
Written by Andreas Ackerl   
Tuesday, 27 July 2010 13:18

If you wondered why you should learn Spanish and scuba dive, here is an eye-opener. Apart from attractions like scenic tourist spots, great food and music, Spain is also the diving capital of Europe. With a favorable geographic location, it offers excellent opportunities for sea diving activities along its Atlantic and Mediterranean coasts. A clutch of islands off Spain are also interesting destinations. The countries in the Americas, notably Mexico and the Caribbean, have taken the cue from Spain and provide custom made holiday packages with a dash of diving and Spanish courses added in.

Scuba Lessons and Language Immersion

If you learn Spanish and scuba dive, it would be an exciting way of learning Spanish by the immersion method. Immersion refers to the process of imparting language skills by acclimatizing the student to the cultural milieu of the native users. In effect, the learners get a first hand experience of the varied circumstances in which the language is used. In this way, they are able to grasp the cultural connotations and evolution of the language. Spain has a long maritime history of adventure, discovery and colonization. No wonder then that the modern countries which have Spanish influence have adopted this affinity for the oceans. Geographic and climatic factors have led them to tailor tourist attractions around the beachfront. Diving is the easiest and therefore the most popular activity.

Certification Available

An array of international diving certifications is available, the popular one being from PADI (Professional Association of Diving Instructors). Make sure that you acquire the required credits so as to become a certified diver. This certification is mandatory for proceeding with diving activities at several centers. Besides, you must pay for diving insurance which is valid worldwide subject to some conditions. Armed with the requisite certifications, you can plunge into the blue sea. You could explore marine life or do it for pleasure. Note, however, that if you learn Spanish and scuba dive, you can savor the experience in true Spanish style.

There are several Spanish language training institutes in cities like Cancun, Mexico and Tenerife, Canary Islands, Spain, where a course is packaged with a diving expedition. Obtain full information about such courses and plan accordingly. This would help you maximize your learning objectives without compromising on fun aspects.

Learn Spanish and scuba dive so that you get a well-rounded understanding of the Spanish way of life. You can be sure that it would be one experience you will remember for the rest of your life making you come back for more.

Source: http://www.scubadivingplanet.com/articles/templates/general.asp?articleid=29&zoneid=1

 
Clearing up misconceptions about diving historical wrecks PDF Print E-mail
Written by Andreas Ackerl   
Sunday, 25 July 2010 14:02

In the world of archeology there are no digs more difficult than those lying beneath watery depths. With land sites archaeologists are sometimes faced with extremely difficult challenges such as such as the environment in Ozette Washington where they found themselves digging through sticky mud and trying to preserve spongy artifacts. Or the Inca site of Machu Picchu where the air is so thin that it’s difficult to breathe, and the sun so intense that it burns the skin almost immediately. No matter how difficult the dry land dig, however, some basic human needs exist in this environment that are simply not there underwater. The most obvious is air and gravity, but there are literally a myriad of other logistical challenges that become apparent when a team goes to plan an underwater dig.

Digging underwater has in fact, proven so difficult that most archaeologists find more reasons to avoid these sites than to dig them. When an underwater site is taken on the team will sometimes resort to extremely complex and costly ends to make it a dry site. They may, for instance, attempt to divert or drain the water from a shallow site, effectively making it a dry land dig, avoiding the challenges involved with a submerged site. Techniques like these are not cheap, and require massive amounts of time and planning so the fact that they are done in the first place tells us that if at all possible any archaeological project is best dug on on dry land. This gives us a hint as to how complex and challenging an underwater dig must be.

Why is it so difficult? Shouldn’t a team just be able to put on some scuba gear and head on down to the site? After all, the bottom of the ocean is silty and soft; shouldn’t that make it even easier to dig? In this study, I will talk about some of the less obvious problems involved in underwater archeology; the ones that people might not think of right away like physiological and mobility issues. I will start by talking about shallow water digging which is usually the simplest, then more on the more complex problems with digging deeper sites in the 100 to 500 feet deep range. I’ll then move on to the most complex challenges with underwater digs that lye in very deep water like the Titanic or the Yorktown. These sites are tens of thousands of feet deep and if it’s not amazing enough that they’ve been found in the first place, the obstacles involved in actually digging them are mind boggling. Finally, I’ll conclude by talking a little about some of the political and moral issues involved in underwater archeology and explain why it is important that these sites are responsibly dug.

In almost all cases, projects that involve digging in shallow water (15-50 feet) are the simplest. They render only slight physiological complexities and divers are usually able to stay down much longer than on deeper dives. This is, however, not to say that they aren’t without their challenges. How for instance, does an archeologist remove the silt covering the artifacts without causing the water around him to become so clouded with sediment that he can’t even see? One might think that you could just brush the silt aside and the water would carry it away but it doesn’t. Once the visibility has been ruined it can take several hours for it to settle again. Underwater archaeologists have had to invent techniques and tools that literally suck up silt, leaving behind the covered artifacts. These giant underwater vacuum cleaners are usually powered by the thrust generated by the boat’s propeller, and the silt is forced by the engine away from the site, while the artifacts are filtered out by a screen on the front of the vacuum hose. (Martin)

Of course if the site is at the bottom of a river or in an area of the ocean where there is a current, the silt is simply washed away by the moving water, but how does the team keep themselves and the artifacts from being washed away as well? I can say from my own experience that fighting against a strong current gets to be exhausting and frustrating after only a few minuets. It is important also to remember that in a current the simple action of the water moving over the sediment will kick it up and ruin the visibility without any help from the divers. When we take this into account, it is no surprise that the sites with the least visibility tend to be the ones with the most current. Archaeologists have gone so far as to build structures around a shallow site that divert the current. This technique does not actually emerge the site, but rather acts as a shield against the current much as a car’s windshield diverts the strong wind from the driver’s face. This allows for a calm area over the site where the visibility will be improved and the archaeologists won’t have to tether themselves to a solid object or swim against the current. (Martin)

Finally there is the concern of air consumption. If the water is extremely cold, a diver must plan for his dive taking in to account that his bottom time will be shorter because his body has to work harder to keep warm, thus needs more oxygen. However, even under ideal conditions, using divers with the most developed breath control, a team can’t really expect a diver to get more than about an hour out of a single 80 cubic foot tank. More tanks can be added to increase bottom time, but it is important to remember that the more tanks a diver must carry, the more difficult it is for him to move around and the more quickly he will grow tired. It is exhausting enough to work in an underwater environment where every movement is met with the resistance of water; the effect is only compounded when more gear is strapped on. It has to be expected then that a diver can only work four or five hours as day and not the eight or ten he would be able to in a dry land environment, thus the project either has to employ many more people, or it will take much longer than a conventional dig.

When it comes to SCUBA (Self Contained Underwater Breathing Apparatus) some unique problems begin to pop up when the diver gets to depths of much more than thirty feet and they become the primary concern at depths in excess of one hundred feet. Since very few shipwrecks lie in shallow water and the cost of diving on an extremely deep wreck is often too great, most underwater archeology in done in water in water ranging in depth from 100 to 500 feet. As any experienced scuba diver will attest to, these are the depths where the danger in scuba becomes most apparent, but they are also the depths where you will find the most interesting things, especially if you are into wrecks. So why is it more dangerous to dive on sites at these depths than those in the fifteen to thirty foot range? One might think that it would be because of the risk of equipment failure or the diver running out of air, but in reality, these are of very little concern. The real danger at these depths come from the way a diver’s body reacts to the pressure from the water above him.

The most notorious of these physiological complications is the bends or DCI (decompression illness). Most people have heard of this, but many who don’t dive don’t understand exactly what it is. Whenever a diver goes underwater, he is under the pressure of the water above him. This is why your ears hurt when you dive to the bottom of a swimming pool. At around thirty feet, the pressure is twice what it is at sea level and it grows greater as the diver descends. As the depth increases and the pressure increases each breath the diver takes consists of air that is denser because of the outside pressure. This means that at thirty feet, the diver is breathing twice as much air as he is breathing at sea level. As we know, our bodies absorb the gasses from the air we breathe into our bloodstream and since normal air is almost all nitrogen, our blood is absorbing more nitrogen than anything else. (McCallum)

Take for instance a diver at sixty feet. With each breath he is absorbing roughly three times the nitrogen of a person on the beach. This doesn’t become a problem however until there is a change in pressure. After all, everyone has a good deal of dissolved nitrogen in their blood at any given point, but we need not worry about it because we know the pressure around us is not likely to change much. With the diver, however, this is not the case. If he has been working at a site lying in 200 feet of water four twenty minuets, he’s been absorbing outrageous amounts of nitrogen into his bloodstream and if he were to suddenly decide to come to the surface, the dissolved nitrogen, like any gas in its liquid form under pressure, would turn back into its gaseous state as the pressure diminished.

As we know, having gas bubbles in our bloodstream is extremely dangerous, and in some cases it can even lead to death, so those planning underwater excavations at these depths must take great care and planning to avoid this dangerous problem. Many divers use, for instance, dive computers which will calculate how much time a diver spent at a given depth with his rate of air consumption to determine the nitrogen levels in his blood and tell him when he must come up and at what depths he must make timed decompression stops to outgas nitrogen. These computers allow divers maximum flexibility in their work because they can dive right up to their physiological limits, yielding the best bottom time. (TDI)

If the site is under water ranging in depth from sixty to one hundred feet, the team may chose to use a special gas mixture called NITROX to yield even more bottom time than can be achieved with normal air. Historically, this gas has been used by the navy and research teams, but in recent years, it has fallen into the mainstream of casual scuba. NITROX doesn’t actually introduce any unfamiliar gasses into the compressed air, but rather increases the oxygen level, replacing some of the nitrogen. This means that if a diver is breathing a 40/60 (40% oxygen and 60% nitrogen) blend, he is dissolving roughly twenty five percent less nitrogen into his bloodstream, allowing him to stay on the site longer. (C.N.P Program)

Why then don’t underwater archaeologists simply breathe pure oxygen and eliminate the nitrogen completely from the equation? The answer is that under pressure, oxygen levels in a divers blood can become too high causing the diver to convulse. As I mentioned above, the deeper a diver goes, the more actual gas he breaths, and at even a very shallow depth pure oxygen will cause blood-oxygen levels to become so great that they are toxic to the diver. NITROX, then is a very customizable gas and a team will choose the best mix for the depth of the site. If, for instance, the site is in eighty feet of water, the team might use a NITROX blend of 40% which would become toxic if the diver was to descend to eighty five, but yields the best bottom times at eighty because of the reduced nitrogen levels. The trouble with NITROX is that it is only beneficial for relatively shallow dives because you quickly reach a point of diminishing return as you go deeper. If a team needs to reach a depth below two hundred feet, even the air we are breathing now has oxygen levels that are too high and would become toxic. (C.N.P Program) How then do teams carry on projects at say three hundred feet?

The answer: use a gas called TRIMIX by partially replacing both the nitrogen and oxygen with helium. This type of diving is highly theoretical and is usually reserved only for the Navy, research teams and highly trained technical divers. However, if the financial and technical resources are available, archeological teams may sometimes use it to conduct their excavations. Since these dives usually involve very long decompression stops on the way back up, and since the gas mixtures consumed at the bottom are often so thin in oxygen that they wouldn’t even support life at sea level, it is not uncommon for as many as eight individual tanks to be used by each diver on a single dive. (TDI) This is extremely expensive and the diver’s bottom time is usually limited to only a few minuets, so the work must be conducted quickly and sometimes with haste, since a high element of danger hangs over each diver’s head. The team usually needs to have a recompression, or hyperbaric chamber on location to deal with any instances of DCI, as well as many diving teams since a single diver may only be able to make one or two.

Again, diving with TRIMIX is extremely expensive. Depending on the blend a single tank of TRIMIX can cost as much as $80, and each diver needs a separate regulator for each blend of gas he breathes. (TDI) Hyperbaric chambers often have to be leased from the government or hospitals and the staff that runs them costs in the realm of two hundred dollars per hour. Each diver is highly trained and faces a strong element of danger, so they don’t come cheap, and the team usually needs a full fledged research vessel just to carry all the gear. These dives are also extremely dangerous. DCI is not an uncommon occurrence, and since the depths they are dealing with are so great, any slight error in planning leads to disastrous consequences. It is not surprising then that only the most glamorous projects at these depths are taken on.

Even TRIMIX reaches a point of diminishing return at about six hundred feet (although at least one person has made it past one thousand breathing it). Thus, for very deep wrecks like the Yorktown, another solution must be found. Without a tremendous budget, raw determination and the latest sonar technology, Pieces of history like the Yorktown and the Titanic can’t even be found, let alone dug. Bob Ballard, above all others, has pioneered this technology, and exemplified the strong will it takes to discover wrecks at these astronomical depths. On his deepest discovery, the Yorktown, he combined a vast array of technological innovations and sheer luck to discover and make the three mile trip down to the ship’s decks. (National Geographic)

So where does an archaeologists begin to take on a project of this magnitude? Well, as it would logically follow, the first challenge is actually finding the wreck. On his search for the Yorktown, Ballard used mostly eyewitness accounts and charts from World War II to outline a one hundred square mile section of midway which he searched by using a massive research vessel to pull a navy sonar module in a criss-cross pattern. As he covered the ocean floor, he took note of anything unusual that came up on the sonar screen and charted them as possible sites of the ship. Once he had the possibilities narrowed down, he attempted to send an unmanned Navy probe into the depths to try and get a first hand look at what he thought was sure to be the Yorktown. He didn’t get his chance this time, however, since four hundred feet from the ocean floor, the probe imploded and needed serious repair. Navy technicians spent days repairing the crippled probe and it was only after the second dive that Ballard was able to confirm that what he had found was indeed the Yorktown. (National Geographic)

Needless to say, not every archeologist has access to a research vessel and cutting edge Navy sonar and submarine technology, so clearly this type of research is left to those like Ballard with the highest budgets. But the cost of a project like this only begins with finding the site. Once the wreck is found, deep diving research subs and costly camera equipment must be obtained to properly map and chart the site. If the decision is made to bring artifacts to the surface it can take years and costly chemicals to properly preserve them. For these reasons, most sites at these depths will never be explored. Tragically, there are simply not enough institutions willing to foot the bill for such expensive research.

Since we can’t have a shipwreck to explore without a wrecked ship, and since the action of a ship wrecking tends to kill people, archaeologists, have to be sensitive to the idea that in most cases these sites should be treated as graveyards. Some archaeologists like Ballard take great care not to disturb the wrecks he finds. He refuses to bring any artifacts at all to the surface and focuses instead on mapping and charting the sites. This “take only pictures, leave only bubbles” mentality shows great respect for those who have perished and their families. The archeologist is still able to discover and learn key facts about the history of the ship or the way it went down but the wreck is left intact.

All too often, however, another team will come in after the serious archaeologists have left and pillage the site. The most notorious of these cases is the Titanic where Ballard, as usual, went to great effort not to disturb the anything, only to have a French team come in later and recover artifacts so they could sell them for a profit. This kind of treasure hunting really is a tragedy, not only because it shows no respect for the people who have died, but because it causes governments to be cautious about letting anyone conduct research in their waters. Countries have had so many artifacts stolen from them in this way that they often assume any archeologist is a treasure hunter and refuse to give research permits to anyone at all.
If our base of knowledge is to continue to grow with respect to maritime history and ship construction, it is absolutely essential that archaeologists are allowed to continue exploring both the very shallow and the very deep wrecks alike. For this to happen, universities and research institutions must be willing to finance these projects, and there must be some world wide provisions put in place to eliminate the trend of treasure hunting so that countries will be able to trust this delicate research to those most qualified. Bob Ballard stands out as a shining example of a good scientist with his priorities firmly in place. He has respect for both the memories of those who died in the wreck as well as the countries who’s waters hold these fascinating sites. Anyone planning an underwater dig would do well to follow his lead.

Source: http://www.scubadivingplanet.com/articles/templates/general.asp?articleid=25&zoneid=1

 
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