A REMARKABLE monument to British naval power that was built on the eve of the battle of Trafalgar 200 years ago is in imminent danger of destruction by developers in Gibraltar.

Under heavy pressure from the Gibraltar Government and the Irish development company OEM International, the Gibraltar Heritage Trust withdrew last week an injunction delaying the construction of a block of 200 flats on top of the Rosia Water Tanks, a series of underground caverns built in 1799-1804 to supply fresh water to Royal Navy ships.

Lionel Culatto, a local historian, says that the tanks are huge and awe-inspiring. “There are six parallel chambers dug out of the natural rock and vaulted in brick brought from Britain. They are about 30 to 40ft wide and over 150ft long. They are floored in flat bricks like Roman tiles. Each tank feeds into the next, so the water was steadily purified.”

The developers plan to destroy the tanks to provide underground car parking for the flats, which will dominate Rosia Bay, where the Victory was repaired after the battle of Trafalgar.

The Gibraltar Government insists that the new flats will do “no harm or damage” to the colony’s heritage, but they will be built next to the 1807 Victualling Yard, the earliest constructed outside Britain.

Ann Coats, of the Naval Dockyards Society, said that the tanks were “a unique engineering monument to Royal Navy ingenuity and Gibraltarian craftsmanship, transforming Gibraltar into an invincible fortress. They enabled Nelson and Admiral Lord St Vincent to maintain their fleets in the Mediterranean, blockading Toulon and vanquishing the French at the Battle of the Nile.”

Jonathan Coad, of English Heritage, the leading expert on the architecture of the Royal Naval Dockyards, said: “The new flats will seriously affect the whole setting of this remarkable enclave and destroy the intimate scale of the area.”

The local residents’ association will decide today whether to continue legal proceedings against the scheme.

Conservationists have appealed to Sir Francis Richards, the Governor or Gibraltar, to list the structure before th bulldozers move in.

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