We have found a lot of burned wood on the OVM 10. This might be the reason for sinking, but maybe it happened only after the ship was deserted. We will probably never know. The structure however must have burned for quite a while, based on the severity of the burning marks on the individual timbers.
The ship parts emerging from the sediment are quite degraded by Teredo navalis or shipworm. The timbers became exposed after the sand extraction for the Maasvlakte 1, but also other activities in the lake. Some structural elements on OVM 10 only became exposed recently due to illegal airlifting. This wood still hasn’t been attacked by the shipworm but is obviously very vulnerable for future attack.
The site has been particularly difficult to research, because it is not structurally intact and pieces of the ship are strewn about the lake floor. A hypothesis was suggested that this did not occur at or around the time of the ship’s sinking but could be a result of the dredging that took place. This could explain why so many of the planks and beams are sticking up out of the sand. The fact that beams and planks are also cracked and splintered at the ends, supports this theory.
The sandy bottom has also been a challenge to our divers who have to be careful not to kick up the sediment when taking measurements as this can decrease visibility. In general, visibility has been reasonable, around 3 meters. This is good enough for our photogrammetry recording.
Today divers took some dendro samples from different parts of the ship. These will be taken away for analysis to determine the age of the wood and where the tree was felled. Analysis will also be done to show the effect the shipworm has had on the wood as well as the bacteriological decay.
Most of the measurements have been taken and entered into Site Recorder and the picture of where each and every detected structure element is positioned is becoming clearer every day. The work the divers have been doing is very accurate and we are happy with the results so far.
Tomorrow some of the team members will be leaving us, so they will be wrapping up their work assignments of the project and saying their farewells.
Robert de Hoop (intern Maritime Program)
Bronwyn Hughes (Leiden University)