Preliminary research by the team, studying historical records, has already identified three British and 41 German submarines from the conflict which are known to have sunk in the area.

The locations of some of these have already been established, but others have yet to be discovered.

Once they have been found, the team will dive onto them to assess their condition. They will then decide whether any measures can be taken to slow down the shipwrecks’ rate of decay on the seabed.

Depending on their historical significance, the vessels may also be added to existing list of shipwrecks covered by the Protection of Wrecks Act, which tightly controls such sites, or scheduled as an ancient monument.

If the vessels sank with men on board, they could be added to the register covered by the Protection of Military Remains Act, to ensure the war graves cannot be disturbed.

Mark Dunkley, a marine archaeologist with EH, said: “These sites may be out of sight, but they are still an important part of our heritage. There are people still around who will have a link to the men lost on these boats.

“They are an important part of family, as well as military, history.

“People might know more about U-boats in the Second World War, but this project will show just what a significant part they played in the first world war – and very close to land.”

The locations of around half of the 44 vessels are known. To find the others, EH is planning to enlist the help of local diving groups around the coast.

Although most associated with the Second World War, submarine warfare was first deployed during the earlier conflict, as German U-boats attempted to cut supply lines into and around the British Isles, while Royal Navy vessels patrolled in search of enemy ships.

At the start of the war, submarines were supposed to abide by international rules which complied them to then allow the crews of merchant ships to get to safety before sinking their vessels.

But this swiftly became impractical and led to the adoption of unrestricted submarine warfare by Germany, which, nearly brought Britain to its knees in 1917.

During the course of the war, German U-boats sank more than 12 million tons of shipping – around 5,000 ships – with the loss of 178 submarines and almost 5,000 men killed.

Most of the wrecks covered by the English Heritage project, which is expected to run throughout the four years of the Great War centenary, are German submarines which were targeting coastal routes, either attacking merchant shipping with torpedoes or laying mines.

They include UB65, which sank HMS Arbutus, a Royal Navy sloop, as well as six merchant ships and damaged six more, before sinking with the loss of all 37 crew near Padstow, Cornwall in July 1918.

The vessel, which went to the bottom after an apparent accident, had been plagued by bad luck and deaths and before its loss the German navy is said to have called a priest on board to perform an exorcism.

They also include UB115, which sank off the coast of Northumberland in 1918 with the loss of all 39 crew, after being attacked by British armed trawlers, warships, and even an airship, R29, which dropped bombs on it.

Several others went down off the east coast, among them UB107, which sank off Flamborough Head in July 1918, either as a result of an attack by British vessels, an accident, or after hitting a mine; UB41, last sighted by the SS Melbourne on October 5 1917 off Scarborough, which is thought to have struck a mine of suffered an internal explosion; and UB75, which had left Borkum on November 29, 1917 for the Whitby area. She succeeded in sinking four ships but never made it back home.

The only three Royal Navy submarines covered by the project were lost in accidents: HMS G3, which ran aground in Filey Bay, North Yorkshire, after the war in 1921; HMS G11, which ran aground near Howick, Northumberland, 1918; and HMS J6, which was sunk in a friendly fire incident, after being mistaken for a U-boat in 1918.

_{A young couple pose for photographs on the wreck of HMS G3 in Filey Bay, North Yorkshire.}

English Heritage has responsibility for all historic wrecks off the English coast, but most of those it cares for are wooden warships.

To find out more about how to preserve the metal vessels from the First World War, it conducted a preparatory survey last year, on the wrecks of two submarines which sank just before the conflict – the Holland No 5, which sank off Beachy Head in 1912 and the A1, which went down in Bracklesham Bay a year earlier.

Both vessels sank without loss of life, although the A1 had previously sunk, in 1904, with the loss of all hands.

Both boats had a hull half an inch thick, but after more than 100 years on the seabed, researchers found these had thinned to as little as a quarter of an inch in places.

The team believe that some wrecks can be preserved by placing on them “sacrificial” anodes, which corrode at a faster rate, protecting the hulls.

Source – The Telegraph