Dogger Bank UXO Removed with Minimum Impact on Marine Mammals

The Royal Netherlands Navy mine hunter HNLMS Makkum has cleared an unmapped ‘Blockbuster’ from World War II. It was found by fishermen at Dogger Bank, about 200 miles offshore the Dutch coast in the North Sea. This type of bomb, weighing 4,000lbs and measuring 2.5m long, was designed to cause heavy damage to buildings. Before clearing the bomb, marine mammals were encouraged to swim away from the area.

An additional sonar was used to generate a high-frequent sound that is unpleasant for them. Also, grenades were thrown overboard to scare them away. Furthermore, the bomb was lifted up to 10m below waterline to reduce the damage of the blast.

Explosives Leaked Away

The expectation was that the blast would cause a huge water column, but this was not the case. A diver was sent out for an observation and the 1,800kg of explosives appeared to have leaked away during the 70 years underwater. Most important was that a potential hazard was removed. The method of clearing was positively evaluated and will be applied more often in the future.

Video courtesy: Royal Netherlands Navy. The video is in Dutch language.