Ballast Water

Studies conducted in several countries have shown that many species of bacteria, plants and animals can survive in viable form in ballast water and sediments on ships, even after voyages of several months. When the ballast water or sediment is discharged into a port state’s water, it can lead to the establishment of harmful aquatic organisms and pathogens that are a threat to native human, animal and plant life and the marine environment. The Swedish Environmental Protection Agency can provide more information about the effects of foreign organisms (species). On the website of the Global Ballast Water Management Programme ( there is more information.

Methods for reducing the introduction of invasive species
Ballast water exchange at sea is one way to reduce the opportunities of fresh water or coastal species to be transferred with ballast water. Technical equipment for treating ballast water with, e.g., UV, ozone, free radicals and/or electrochemistry are being developed all over the world, but it will be some years before this equipment is widely available on the market.

The technique must also be approved in accordance with the International Convention for the  Control and Management of Ships' Ballast Water and Sediments.