The bottom has been reached: Drone inspection of the tunnel trench
DHI has had an underwater drone down to inspect life on the seabed in and around the tunnel trench. Photo: Femern A/S via LinkedIn.Photo: Femern A/S via LinkedIn.
Bernt Hertz JensenBerntHertz Jensen
PublishedModified
Marine environment specialists from DHI (Danish Hydrological Institute) have sent a small unmanned submarine – also called an underwater drone or an ROV – down to the tunnel trench near the southern coast of Lolland. The purpose of the expedition was to examine the state of the marine environment around the tunnel trench after a few years of intense excavation work.
Poor visibility The waters around Denmark – especially the western Baltic Sea – are not exactly the Mediterranean or a coral reef in Oceania. The water is murky, and visibility is often less than a meter. Therefore, we unfortunately cannot provide dizzying images of the deep trench on the seabed or of fish and other marine animals in free movement.
The recordings in and around the tunnel trench will be used to continuously monitor life in the water around the tunnel both before, during, and after the construction work.
Visibility is low in the western Baltic, so it’s so-so with the spectacular and brightly colored images. But there is life down there. Photo: Femern A/S via LinkedIn.
Tracking development “This ensures us a benchmark so we can track the development of marine life over time. It provides us with valuable experience for future projects. By carrying out these studies, we can closely follow how the marine environment develops before and after the tunnel is in place and covered. Especially near the coasts, the protective layer of stones above the tunnel will become feeding and breeding grounds for marine wildlife,” writes Femern A/S in an email to FemernReport.
There is Life The drone footage shows that there is life around the tunnel trench. However, it is inevitable that Northern Europe’s largest construction project leaves its mark.
“During the recordings, we encountered several crabs and some flatfish. And seaweed. The latter is not a given according to marine biologists. It can take five to ten years for nature to reclaim areas of this type. But the fact that there is already life down there is seen by the experts as a positive sign that the development in the Fehmarn Belt may progress faster,” writes Femern A/S.
