Wreck diving, the sense of seeing history, where time has almost stood still underwater is nothing if not fascinating
Wreck diving is, and forgive me for being obvious, the description for scuba diving specifically on or around sunken ships, whether ships wrecked accidentally or those, which are becoming increasingly common, sunk intentionally to create an artificial reef.
The attraction for wreck diving comes from several aspects amongst which is the fact that the structure creates an artificial reef with ample suitable habitat for sea life, where the habitat may not have existed before.
The historical perspective of many these wrecks holds many entranced as we view a 'snapshot' of past maritime life.
A world famous wreck, the SS Thistlegorm is a particularly interesting location for wreck diving, lying in the Red Sea having been sunk during the second world war. The following is the account of her sinking I have taken from Wikipedia:
She set sail on her fourth and final voyage from Glasgow on 2 June 1941 destined for Alexandria, Egypt.
The vessel’s cargo included: Bedford trucks, Universal Carrier armoured vehicles, Norton 16H and BSA motorcycles, Bren guns, cases of ammunition, and 0.303 rifles as well as radio equipment, Wellington boots, aircraft parts, and two LMS Stanier Class 8F steam locomotives.
These steam locomotives and their associated coal & water tenders were carried as deck cargo and were for the Egyptian Railways. The rest of the cargo was for the Allied forces in Egypt. At the time the Thistlegorm sailed from Glasgow in June this was the Western Desert Force, which in September 1941 became part of the newly formed Eighth Army.
The crew of the ship, under Captain William Ellis, were supplemented by 9 naval personnel to man the machine gun and the anti-aircraft gun.
Due to German and Italian naval and airforce activity in the Mediterranean the Thistlegorm sailed as part of a convoy via Cape Town, South Africa, where she refuelled, before heading North up the East coast of Africa and into the Red Sea. On leaving Capetown, the light cruiser HMS Carlisle joined the convoy.
Due to a collision in the Suez Canal the convoy could not transit through the canal to reach the port of Alexandria and instead moored at Safe Anchorage, in September 1941 where she remained at anchor until her sinking on 6th October 1941. HMS Carlisle moored in the same anchorage.
There was a large build up of Allied troops in Egypt during September 1941 and German Intelligence, Abwehr, suspected that there was a troop carrier in the area bringing in additional troops.
Two Heinkel He-111 aircraft were dispatched from Crete to find and destroy the troop carrier. This search failed but one of the bombers discovered the vessels moored in safe anchorage.
Targeting the largest ship they dropped two bombs on the Thistlegorm both of which struck hold 4 near the stern of the ship at 0130 on 6th October.
The bomb and the explosion of some of the ammunition stored in hold 4 led to the sinking of the Thistlegorm with the loss of four sailors and five members of the Royal Navy gun crew. Mr. Rejda single-handledly saved most of the sailors by swimming in to the wreck and towing them to safety.
The survivors were picked up by HMS Carlisle. Captain Ellis was awarded the OBE for his actions following the explosion and a crewman, Angus McLeay, was awarded the George Medal and the Lloyd's War Medal for Bravery at Sea for saving another crew member.
Most of the cargo remained within the ship, the major exception being a steam locomotive from the deck cargo which was blown off to the port side of the wreck.
The amazing thing about wreck diving here is the fact that all of the items described in this account can be seen - the locomotives lie on the sea bed, the anti-aircraft guns are still mounted. Bedford trucks and as in the photo above - motorcycles with their tyres clearly intact.
Wreck diving presents different challenges for the scuba diver, it can be hazardous.
There are different levels of wreck diving often depending on the type of wreck itself as to whether the type of activity is possible or not.
Some wrecks are older and as such the marine growth has sealed the hulk up where penetration is not possible
Other wrecks are in a hazardous state of decay where penetration is not advisable beyond a very superficial level of penetration.
It is generally the case that wrecks deteriorate faster at shallower depths due to the increased marine activity when compared to deeper wrecks, this then would apply to recreational wreck diving as against would then be technical diving required for greater depths which probably include decompression dives with side mount cylinders, and a significantly more complicated set of knowledge skills.
It is advisable to undertake wreck diving specialty courses to gain the knowledge of the hazards of wreck diving in order to safeguard oneself against the dangers which may present themselves when diving in and around a structure which has the facility to harm a diver in several ways:
The diver may get snagged on protruding infrastructures or perhaps rope or netting.
The wreck may have parts which move in the current or indeed be loose as well as sharp potentially causing injury to the unwary.
Diving within the structure can result in the additional dangers of becoming disorientated and lost through lack of light or disturbed silt.
I was recently diving on a wreck off the coast of South Africa where the wave surge was unexpectedly strong.
Granted the swell on the surface was quite big at probably four meters – when we were diving at 19m a surge came through which carried the dive master a distances of 5 or 6 meters in a matter of an instant. Another diver got tangled in a rope suspended above the main infrastructure. These incidents may well have resulted in serious injury had the divers involved not been very experienced and been taking appropriate precautions to ensure they were aware of where they were in relation to the wreck superstructure as soon as it became apparent that the swell was having a significant impact that deep.
Wreck dive essentials:
- Never dive a wreck alone!
- Many of the more attractive wrecks are in deeper water so deep diving skills are often required with close attention being paid to bottom time limits and the dive plan.
- It is a good idea to have a knife as well as a spare source of light.
- Good or safe air management is essential.
A guideline for air management is one third of air supply is used for getting down and into the wreck.
The second third is for exiting the wreck and for the ascent to safety stops.
The last third is kept for reserve.
Excellent buoyancy control is paramount, when you are moving in restricted spaces you do not have the luxury of being able to move up and down to any degree without risk of either snagging on structure above you or possibly stirring up silt which may blind you.
In complex wrecks, perhaps even in not so complex wrecks, a guideline may be used to ensure exit points may be relocated – getting disorientated may result in catastrophe.
Even if a diver has ample lighting, silt stirred up may reduce visibility so a torch becomes useless – in those instances a guideline would be the only sure way of finding your way back out of the wreck in time.
A point to remember is that most wrecks fall under some sort of protection regulation by the authorities, both from a protection of the asset as well as safety of the individual.
Salvaging items from a wreck may expose a diver to prosecution due to the historical nature of the wreck, the fact that the wreck may be considered a war grave, the wreck may be considered to be owned by a party. In addition to this some wrecks may be considered to be too dangerous to dive unless specifically licensed by the appropriate authority.
To read about other types of recreational diving like Wreck diving, click here