HMS Scylla, the last warship to be built in Plymouth’s Devonport Royal Naval Dockyard finally came to rest on the seabed in Whitsand Bay, Cornwall; not as a result of an incident or an accident but as the culmination of a carefully planned and deliberate programme to turn her from a beautifully designed surface vessel to an undersea artificial reef.

Following a distinguish naval career Sylla was deemed to have reached the end of her active life and became available, a fact identified by a group of local people from the dive community who wanted to extend her life, but on the seabed as a dive site.

If the purchase had not been successful she might have ended up as razor blades or as a target for practice.

The National Marine Aquarium became involved as the responsible body that could manage the project and administer the public funds used to buy the ship and prepare her for placement.

The regulations concerning disposal of vessels are, quite rightly, strict; being designed to minimise any future risks to shipping and the environment, and the funding bodies were nervous of placing such responsibility on a few individuals.

As far as the National Marine Aquarium was concerned the fit between its educational aspirations and the creation of an artificial reef was an easy one. After all part of the charitable remit for the Aquarium is to highlight “man’s interaction with the oceans” – the placement of Scylla was a great opportunity to further this aim.

The Aquarium team with its experience and skill base was ideally suited to carry out the project.

The total cost of the project was close to £1.2 million of which £200,000 was the purchase price of the ship; the remainder was required to clean her to acceptable environmental standards and to prepare her as a dive friendly reef.

All potentially hazardous materials such as hydrocarbons were removed and a series of access holes were cut into the hull. Poignantly the work to prepare her was carried out in the very dockyard where she was built, and at least some of the team had worked on her originally.

Devonport Management Ltd. executed the work to a tight schedule, maximising the salvage value of specialist metals and equipment where appropriate to bolster the costs. Throughout the project advice was provided by a team – The Canadian Artificial Reef Consortium – who had carried out similar projects elsewhere, and who had particular experience with determining the positions and setting of explosive charges.

The end result was a compromise between diver safety and accessibility as well as retaining a challenging environment for divers of varying skill levels. Some areas, deemed to be complex challenges for divers, were closed off, one such is the boiler room which contains many potential snags.

An interesting challenge was the insurance. Scylla had to be insured as she was towed from her Portsmouth berth, during the cleaning and preparation in dry dock and throughout the final journey from dock to seabed.

Not surprisingly the insurers found the challenge of insuring a ship that was destined to be sunk as somewhat unusual.

The area for the placement was chosen after careful consideration and a broad series of surveys including diver visits, video and hydrographic surveys. It was essential to make Scylla accessible, she rests in about 20 metres, is close to shore (about 1 km) and is within easy reach of dive operator bases in Plymouth and South East Cornwall.

The lay of the seabed to ensure an upright position and no risk of breaking up on placement was also essential. The final site was agreed in Whitsand Bay, after discussions with The Marine Coastguard Agency and the Crown Estates in particular but with other discussions amongst government and non-governmental organisations.

Watched by an estimated 100 million TV viewers and reported internationally in the press Scylla was placed in a blaze of explosions, surrounded by a flotilla of vessels and crowds of coastal onlookers onto the seabed on Saturday afternoon of March 27th 2004.

Within just hours the first animals began to move in, a crab and a ballan wrasse they were the first of a gradual succession of organisms that now encrust the surface and inhabit each crevice. Many species use the vessel for shelter or visit from the surrounding waters.

Economic estimates suggested that Scylla would generate around £1 million/annum into the local economy through accommodation, dive boat hire, equipment purchase etc. divers hoped that she would provide a new and exciting dive venue; biologists anticipated a laboratory on the seabed to monitor local conditions and the colonisation sequence of a ‘shipwreck’; the National Marine Aquarium through cameras beaming live images back from the seabed required a live connection from ocean floor to aquarium visitor.

Within her first year Scylla has lived up to all of these expectations, and the signs are that she will continue to do so into the future. Hindsight is a wonderful thing but so is belief in a project and the enthusiasm and skills to carry it through. Target practice? Scrapped on a foreign shore for razor blades? Economically, biologically and recreationally successful artificial reef? No need for the question really – is there?

Kelvin Boot is Aquarium Director at the National Marine Aquarium, Plymouth UK

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