Distribution of First World War wrecks within the Devon study area (image credit: Contains public sector information, licensed under the Open Government Licence v2.0, from the Maritime and Coastguard Agency).
As part of the Forgotten Wrecks project this summer the Maritime Archaeology Trust sent out a team of divers to find and document a number of WW1 wrecks off the South Devon Coast. In order to assist the divers in finding these wrecks bathymetric maps were consulted. Much like navigational charts used by mariners these maps show the topographic features of the seafloor. However, modern techniques such as multibeam bathymetry, paint a far higher resolution image of the seafloor with measurements made every few metres. As a result, even fine details such as the orientation of shipwrecks and the positions of larger objects such as boilers and anchors on these sites, can be seen.
Within the area surveyed by the Maritime Coastguard Agency between 2012 and 2015 (data freely available from aws2.caris.com) 31 of the 48 wrecks which had been identified as lying within the south Devon study area reviewed ahead of diving operations were visible.
Once identified a zoomed in map was created of each wreck. The examples shown here are of the British Navy trawler, the Benton Castle and cargo ship, the Newholm. Both of which sank after hitting mines, leading to the loss of 30 lives in total. These images and images of the other wrecks were used by the diving team to help select individual sites to dive and then plan their dives more effectively.
Geophysical survey image of the Benton Castle (image credit: Contains public sector information, licensed under the Open Government Licence v2.0, from the Maritime and Coastguard Agency).
Geophysical survey image of the Newholm (image credit: Contains public sector information, licensed under the Open Government Licence v2.0, from the Maritime and Coastguard Agency).
The dive team operated out of Dartmouth using Falcon Diving Charters (http://falcondivingcharters.com/) during the week of 27th June to the 1st July. Despite some challenging weather conditions the team managed to reach a number of the Forgotten Wrecks to undertake survey and photogrammetric recording.
Written by Amelia Astley
To find out more about the Forgotten Wrecks of the First World War project, click here.
Diver photographs detail of the wreck structure of the Newholm.
Marine life encrusts the remains of the wreck of the Benton Castle.
Another day on Bouldnor Cliff reveals another exciting discovery. Garry Momber took part in the day’s first dive, and began to clear away some of the layer of mud covering the site. Underneath this mud he found a series of planks lying parallel to each other. Further dives will include more work on this potential platform, so the archaeologists can try to interpret the feature and its purpose. Yesterday, a diver found and recovered a small piece of flat, pointed timber that may turn out to be the end of a plank. Garry also recovered a small piece of wood, demonstrating the excellent preservation on this site. It is still possible to find organic material that is over 8,000 years old!
Miguel, Ziad, and Mohamed are still hard at work on the photogrammetric work. Miguel has been acting as underwater photographer, taking pictures of Garry at work and using a 6m x 2m grid to take photos to create a photogrammetric model of the site and some of the exposed timbers. Ziad and Mohamed are doing similar work, both with and without photogrammetric targets. The divers are working hard to ensure they don’t damage any of the exposed timbers as they do their work, and are being careful where they use targets. In places where the timber is fragile, it may be better to work without them. Eventually, the hundreds of photos taken will be combined together. They will be used to create a 3D model of the Mesolithic site, which can be manipulated and interpreted, and used for further study.
