Scanners reveal a wreck on the bottom of Lake Geneva
The Russian submersibles involved in EPFL’s elemo project have discovered a new wreck on the bottom of the lake. Underwater archaeology is benefiting from scanners developed for scientific research.
“It’s always a memorable moment when you find an unknown shipwreck. It’s not on the maps, and after having gone around it, I didn’t see any inscription on its hull,” explains Evgeny Chernyaev, who was piloting the submersible.
Diving off the shores of la Tour-de-Peilz, he was taking sediment samples.
The sonar indicated a large object off to one side. It was a sunken boat. The team was lucky; the portholes provide only a very limited range of vision and the sonar only sweeps 200m in front of the submersible, with an arc of 90°. The wreck is most likely an old barge used for hauling stone or gravel.
“The boat, about 30 meters long, could date from the end of the 19th or beginning of the 20th century. It must have sunk while navigating, because the anchor and other components were still on board, whereas boats that were sunk deliberately would have been stripped of all useful equipment,” explains Carinne Bertola, from the Musée du Léman in Nyon.
Bertola, a specialist in shipwrecks, thinks that it was an old barge that transported materials extracted from quarries in the St. Gingolph area.
The pilot confirms this: “The state of the wreck leads me to think that it dates to the same time as that of the Rhône, which is not far away.”
At the bottom of the lake, where objects are covered in sediment and the visibility is bad, explorers can easily go right by a discovery. Fortunately, during this dive, Marie-Eve Randlett from EAWAG and Don Dansereau from the Australian Centre for Field Robotics were using a high-resolution scanner.
This instrument helps them position the submersible correctly to take sediment samples at the desired depth, as well as make a precise map of the lake bottom.