German Federal Agency for Nature Conservation (BfN)


Oil and gas prospecting and extraction

A6B4 gas rig near Dogger Bank. Photo: BfN
A6B4 gas rig near Dogger Bank. Photo: BfN

Oil and gas prospecting and extraction activities in German waters have so far largely been restricted to the North Sea. Most of the test drillings have failed to uncover commercially exploitable resource deposits.

Drilling takes place from fixed or mobile rigs, using water-based or oil-based drilling fluids. With water-based methods, drilling debris and flushing water are disposed of in the sea. With oil-based methods, they are disposed of on land for environmental reasons.

Seismic reconnaissance surveys impact marine biodiversity

Extensive seismic surveys are carried out before drilling starts. Very high amplitude sound waves from air guns bounce back from the various layers of the sea floor to indicate the presence of any deposits. Some 4,276 km2 of the German North Sea EEZ has been surveyed since 1997 using 3D seismology alone. That is about 15 percent of the total area. Seismic surveys cause the greatest of all impacts of anthropogenic underwater noise on the marine environment (see Underwater noise).

Oil and gas extraction in German seas

The only active oil rig in the German North Sea (Mittelplate) is situated near to the coast in the Schleswig-Holstein Wadden Sea National Park. It was approved before the creation of the national park and is therefore covered by an exemption.

Natural gas has been extracted on Dogger Bank since 2000. The gas is piped directly to the mainland. 

Between 1993 and 2009, gas was extracted at the mouth of the River Ems (in the Dukegat channel) on the unmanned Manslagt Z1 gas rig. Dismantling of the rig began in 2012.

In the German Baltic Sea, oil was extracted from 1984 to 2000 via the now dismantled Schwedeneck A and Schwedeneck B oil rigs some 4 km off the eastern coast of Schleswig-Holstein.

Environmental impacts

Prospecting and drilling activities have notable impacts on the sea floor, water, benthic organisms and fish.

Pile driving of well conductor pipes generates powerful noise emissions that have wide-ranging impacts on marine mammals. Seismic reconnaissance surveys are even worse in this regard. Pile driving can cause temporary hearing loss and deafness in animals. It can also drown out intra-species sound communication, especially among marine mammals. See Impacts on marine species in Offshore wind power.

Service vessels and the above-mentioned sound emissions can also frighten away marine mammals, fish and birds.

Flaring of unusable gas produced together with oil can attract migratory birds in conditions of poor visibility or at night. This can lead to birds being harmed during mass migrations. Similar problems involving visual signals during bird migration are covered under Impacts during construction and operation in Offshore wind power.