The Baltic Sea probably contains the world’s largest concentration of mines, ammunition and chemical weapons from the two world wars which even today is still dangerous if encountered.
The link “Risk areas” gives a more detailed illustration of those areas within Swedish territorial waters and the Swedish economic zone where the risk of encounter is increased. This information is produced by the Swedish Military authorities in cooperation with the Swedish Maritime authority and the Swedish Transport authority.
The military authorities together with the Swedish coastguard and National Police Board have an earlier government mandate to publish information on mines in general and what to do in the event of encountering mines, unexploded ammunition or chemical weapons at sea. The mandate was given after an incident in Gothenburg where a trawler picked up a mine in the vicinity of the harbour causing large areas of the town to be cordoned off.
This has resulted in a brochure for people in maritime occupations on, amongst other things, what to do in the case of an encounter with a potentially dangerous object. The military authorities can give more detailed information on mines to contractors planning seabed activities.
There is a joint venture between military authorities in the Baltic Sea area with the object of localizing and disarming mines.
More information on mines, unexploded ammunition, chemical weapons and what to do in the case of an encounter can be found in the pdf-file “Information to the public on unexploded munitions” and links to the left.