Facts and Figures

Client
TenneT Offshore GmbH

Period
2012-2013

Location
Between Borkum and Memmert

Contractor
Heinrich Hirdes EOD Services GmbH

Riffgat / Osterems

TenneT Offshore GmbH commissioned Heinrich Hirdes EOD Services GmbH to dispose of explosives along the network connection route for the Riffgat wind farm to the north east of the German mainland.

Cable route in the East Frisian Wadden Sea

At the end of World War II, the allied forces ordered German munitions to be destroyed. This led to the creation of dumping areas in the North Sea and Baltic Sea for all kinds of munitions. Part of the network connection route is very close to one of these munitions dumping areas, see red section on map.

Investigations have shown that part of the dumped munitions are located outside the designated dumping area. The probable reasons for this are:

  • inaccurate dumping of the munitions at the time,
  • the munitions may have been moved by trawler fishing and
  • sea currents may have shifted the munitions on the seabed.

We recover the explosive ordnance we find using the latest technology and extremely high safety standards for our staff. For the recovery work, we use HD-WROVs (Heavy-Duty Work-Class Remotely Operated Vehicles) and underwater electromagnets.

HD-WROV
Underwater electromagnet
Recovered 28 cm HE projectile
Recovered 12.8 cm projectiles