ScottishPower Renewables and Vatenfall, two windfarm developers, discovered an uncharted wreck of a WWI German submarine which went missing in 1915.
The wreck discovered within the East Anglia Zone is 57.6 metres in length, 4.1 metres in width and 4.6 metres in height and the bow appears to be facing south. Damage was observed at the bow and the stern, so the original length could be slightly longer than it appears and debris surrounding the wreck suggests a more likely length of over 60 metres (but less than 70m).
The Royal Netherlands Navy was notified to investigate whether it was Dutch military submarine HNLMS O13, which went missing in action in June 1940.
GoPro footage taken by the Dutch Navy divers highlighted clear images of the conning tower and deck lay-out, which suggested the wreck was of German origin. From German drawings it was identified that this was a WWI German submarine: Type U-31. A database of reference books shows that only U-boats U-31 and U-34 had been lost in this area of the North Sea.
Three years after its initial discovery (in September 2012) the wreck was officially identified as a German submarine, U-31, which left for patrol on January 13, 1915 never to return. The wreck is approximately 90 km offshore in the North Sea but sits on the seabed at a depth of only 30 metres.
Andy Paine, Vattenfall project director of East Anglia Offshore Wind Farm comments: “Following the discovery the team reported its findings to the relevant authorities, including RoW (Receiver of Wreck) in the UK. The seabed scanning had been undertaken by Netherlands-owned company Fugro, and their team made us aware of the Dutch Navy’s hunt for its last remaining missing WWII submarine.”
Commander (Retired) Jouke Spoelstra of the RNLNavy/Submarine Service, who heads up project ‘Search for O-13’ added: “It wasn’t an easy job and several dives were required before any real progress was made due to the sea conditions surrounding the site meaning we couldn’t obtain any evidence revealing the exact identity. Fortunately on a recent dive undertaken by the Lamlash North Sea Diving team they had good conditions and so were able to achieve clear footage and finally identify the wreck.”
SPR and Vattenfall used sonar technology to scan over 6,000km2 of the seabed for their projects off Norfolk and Suffolk, UK. This work is critical to understand seabed conditions, and allow the companies to design the layout of their proposed projects. Although more than 60 wrecks were discovered during the scanning work, most of these were anticipated, but the uncharted submarine 90 km from shore was entirely unexpected.