Jul 2019

An Introduction to Wreck Diving

By Mike Waddington

PADI and other dive agencies generally have a similar structure when it comes to diver education.

You begin your diving career as an Open Water Diver, taking your first underwater breaths and seeing all the amazing life that normally inaccessible to us land dwellers. Then you progress to you Advanced Open Water (or equivalent) and focus on improving what you already know – better buoyancy control, navigational exercises and so on.

But what next? After your Advanced Open Water, the educational structure gets far less linear, and it is up to you to choose where diving will take you. Naturally, many divers will take their Rescue Diver program, as it does make better divers, and many divers may wish to follow the professional path and become certified as a Divemaster or Instructor.

More recently, most diving agencies have started offering speciality courses, where the diver can pick and choose to follow whatever interests them the most. One of the most popular speciality courses available is the Wreck Diver course – a program designed to teach you to safely penetrate underwater wrecks.

What is Wreck Diving?

Wreck diving is exactly how it sounds – diving into a wreck. Be it the wreck of a ship, submarine, aeroplane, or any other man made object that some how ended up underwater.

The historical factors around some of these shipwrecks is the reason why some people want to get into diving in the first place, and with with their eerie corridors, jagged edges, crumbling structure and often a tangled mass of nets, it is easy to see why wreck diving tends to appeal to the more adventurous divers out there.

Although exciting, wreck diving (or any other form of overhead diving) offers new challenges and new hazards to the diver, and it is essential that anyone considering entering such an environment is not only properly trained, but also properly equipped.


What are the Hazards of Wreck Diving?

This short list will highlight some of the hazards of wreck diving, and how to avoid injuring yourself on them.

Overhead Environment.

Anytime you penetrate a shipwreck, you are in an overhead environment. This means you can no longer access the surface by swimming up. Should an emergency happen during the dive, you must first exit the wreck before ascending to the surface.

One of the most important aspects of wreck diving is that you and your buddy can keep calm in any situation. Proper gas management can help minimise risks, as can following your certification level. Most basic wreck certifications allow the divers to a maximum of 40 metres from the surface. This means if the entrance to the wreck is 15 metres below the surface, you will have 25 metres allowance to explore inside the wreck. Following this rule greatly increases your chances of getting out, should anything go wrong.

Before entering an overhead environment it is important you evaluate the state of the wreck. Over time, metal will fall apart, and it is not unheard of for wrecks to break up and fall apart. This is not only true of physically entering the wreck, but also covered areas outside the wreck that form a swim through.

Loss of Direction.

Many divers associate getting lost underwater with cave diving, however, a large wreck can be just as much as a labyrinth as any cave, and with other hazards present, they can be even more dangerous.

Just like Hansel and Gretel leaving a trail through the woods, we always leave a trail for us to find our way out, although we don’t use pebbles or breadcrumbs. Instead, we use a reel, which we use to set up a line to follow on the way back out.

A properly set up line should always start from outside the wreck, where you have direct access to the surface, and should be tied off to something that will not budge. From there, the line is unraveled into the wreck, and tied off at any junction or when it seems to be getting too long. It is important the line does not accidentally snag in a small area where the diver cannot fit through -this is called a line trap.

The diver laying the line should be the first one in, and the last one out. Should any major problems occur during the dive and you need to exit, you simply leave the line where it is and follow it out. If possible, you can return another day to collect it.

Sharp Objects.

Wrecks are usually made of metal, and over time, the water surrounding the wreck will erode it, and sometimes it will form jagged edges. These jagged edges can cut and damage not only your equipment, but also you and even your guideline!

To avoid damaging yourself or your equipment, you must be very aware of how much space you take up inside the wreck, and take care not to crash into anything. You should keep everything tucked away to avoid snagging and cutting anything -especially hoses such as your alternate air source or pressure gauge.

You can help protect yourself from sharp edges by covering up and wearing a full length wetsuit. Gloves are also recommended as you may need to touch the wreck in order to lay your line or stabilise yourself.

Entanglement Hazards.

Most wrecks you will encounter are completely covered in fishing line and ghost nets. This is because wrecks make great artificial reefs, and fishermen soon learn that they can catch a lot of fish around them. Although fishing tends to be banned on wrecks commonly used for diving, it is often the fishermen that find them in the first place, so they are already covered by the time divers get to them.

Inside the wreck, entanglement hazards can still present a problem. Most wrecks you can actually penetrate are modern, and are full of electrical cabling that you can easily get snagged on. Even the line you lay can become an entanglement hazard if it way laid too loose.

Before considering any wreck penetration, you should make sure you have at least one cutting tool -preferably two – and you can reach it with either hand.

Loss of Visibility.

As previously mentioned, most wrecks you will dive on are made of metal, and over time that metal will erode. Covering the floor of most wrecks is a very fine layer of particles, which is known as silt.

Stirring up this silt is not the same as stirring up the sand. It will instantly block out all light, and the finer the silt, the longer it will take to settle on the bottom. Being in a ‘Silt-Out’ is comparable to covering your mask in parcel take and trying to find your way around. Sure, you might see some light, but good luck trying to work out where it is coming from.

Your main safety net here is the line, which you should always keep within arms reach. If a silt out happens, simply grab the line and follow it back out of the wreck.

You can avoid silt-outs all together by paying attention to your buoyancy. Make sure you are not touching any of the surfaces, and pay special attention to your fins. The classic flutter kick has no use when penetrating wrecks, as the up and down motion will drive water to the bottom and will stir up the silt. Your best option is either the frog kick, or modified frog kick, as these propulsion methods direct most of the water behind you, rather than up and down.

Watch your Depth.

While the entrance of a wreck may only be 12 metres or so, a couple of staircases can easily lead to far greater depths. The deeper you are, the faster you will use your gas, and the shorter your no decompression limit is, not to mention throwing narcosis into the mix.

It is very easy to go too deep during any dive, but especially a wreck dive when you loose many references you would normally have outside the wreck. A good way to avoid this is to set depth alarms on your dive computer. This way you will get warnings anytime you approach your maximum depth.


Is Wreck Diving Dangerous?

Yes and no.

Any form of scuba diving or free diving can be extremely dangerous if you ignore the basic rules, however if done properly you have nothing to fear.

Before beginning any wreck diver training, you should already be very comfortable in the water, and be able to do multiple tasks at the same time without losing control of your body positioning or buoyancy. Task loading can be a big part of wreck diving, and you should have all the basics down to second nature before you begin taking on more complicated tasks.

Where is the Best Place for Wreck Diving?

It doesn’t really matter where you are from, there is amazing wreck diving all over the world.

Both Chuuk Lagoon in Micronesia and Scapa Flow in Scotland are frequently named as the best wreck diving locations in the world. Scapa Flow might be a bit too challenging for newer divers, but experienced divers can see some of World War I’s greatest wrecks.

If you prefer easier diving, and Micronesia is out of your range, you might want to visit these other famous and easy to access wrecks.

Obviously there are many, many more, however these famous wrecks tend to be high up on many wreck divers bucket lists.

Do you have any exciting wreck diving tales you would like to share with us? Maybe a secret wreck you know of that you want to world to see? Let us know in the comments section below, and we will be sure to get back to you.

‘An Introduction to Wreck Diving’ was written by Mike

Photo credit: Michela Di Paola & Aquaworld.com

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Mike Waddington

I first discovered diving in 2008 after going snorkeling on the Great Barrier Reef in Australia. After trying diving at a flooded quarry in England I decided to head out to warmer more interesting waters in Thailand where I ended on the Island of Koh Tao completing my Open Water course. Instantly addicted with money to spend and plenty of time on my hands I decided to continue until I became a Divemaster so I could live what seemed as the perfect life.

After that I headed to the Caribbean to an island called Utila to complete my instructor course, I spent several months out there completing the MSDT internship, teaching students and leading dives. This is also where I discovered my interest in the technical side of diving, taking part in equipment repair courses and learning about blending gasses and running compressors.

With all my new qualifications it was time to head back to where it had all started, Back to Koh Tao where I intended on living the dream. Once I arrived I quickly found a job and started teaching straight away. During my time on Koh Tao I took part in all many technical diving courses, learning how to dive with re-breathers, in caves and even going down to 90m/300ft!


PADI Master Scuba Diver Trainer
PADI/DSAT Tech Deep Instructor
PADI/DSAT Gas Trimix Gas Blender
PADI/DSAT Trimix Diver
TDI Intro to Cave Diver
TDI Advanced Wreck Diver
TDI Inspiration rebreather Decompression Procedures
PADI Professional Videographer
BSAC Compressor Operator
TDI Equipment Service Technician

Dream Dive Locations:

Silfra, Iceland
Cenotes, Mexico
Chuuk Lagoon, Micronesia
Ice Diving in Russia