Century-old German submarine continues to leak TNT into the North Sea

The German U-boat UC-30, lost in April 1917 near Rømø, was discovered a century later and has become a focus of the NorthSeaWrecks research project. Samples of water, seabed material and organisms collected by navy divers revealed measurable TNT levels emanating from the wreck and its onboard mines. Professor Katrine Juul Andresen of Aarhus University says the pollution is currently localized but will likely intensify as the hull continues to deteriorate.

Denmark’s Environmental Protection Agency has identified over 10,000 wrecks in its waters, many from the world wars, and acknowledges the potential need for remediation. While Germany has begun recovering explosives from some sites, the process is costly and sometimes risky, leading researchers to explore robotic solutions through the EU-funded REMARCO project. Ultimately, authorities must prioritize which wrecks pose the greatest ecological risk before deciding on removal or containment strategies.