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Ballast Water

Background of the issue

Ballast water is essential for the safe operation of ships. It provides stability and manoeuvrability during a voyage and during loading and unloading operations. Management of Ballast Water also reduces the hull stress caused by adverse sea conditions or by changes in cargo weight as well as fuel and water. However, the process of loading and unloading untreated ballast water poses a major threat to the environment, public health and the economy.

This is due to the fact that ballast water is a vector for the transfer of many organisms between ecosystems, from one part of the world to another. When ballast water is taken up in port many microscopic organisms and sediments are also introduced into the ships ballast tanks. Many of these organisms are able to survive - some of them can even use the uploaded sediments as a substrate – and, when ballast water is discharged, they are released into the environment. If suitable conditions exist in this release environment, these species will survive and reproduce. These are invasive species and in some cases there is a high probability that the organism will become a dominant species, potentially resulting in: the extinction of native species, effects on local or even regional biodiversity, effects on coastal industries that use water extraction, effects on public health and impact on local economies based on fisheries. There are several recorded examples throughout the world of invasive species threatening or even devastating local food sources based on fishing, resulting in impoverished local economies.

Global action

Canada and Australia were among the first countries to experience particular problems with harmful aquatic species, and they brought their concerns to the attention of IMO's Marine Environment Protection Committee (MEPC) in the late 1980's. Shortly thereafter, the United Nations Conference on Environment and Development (UNCED), held in Rio de Janeiro in 1992, recognized the issue of invasive species as a major international concern. In 1997 the MEPC adopted "Guidelines for the Control and Management of Ships' Ballast Water to Minimize the Transfer of Harmful Aquatic Organisms and Pathogens" (MEPC resolution A.868(20)).

The IMO members were requested to ask ships to follow these Guidelines, which called for the exchange of ballast water in the open ocean to reduce the risk the transfer of harmful species. The Resolution also requested the MEPC to keep the Guidelines under review with a view to developing internationally applicable, legally-binding provisions. Finally after many years of negotiations, the International Convention for the Control and Management of Ships' Ballast Water and Sediments (Ballast Water Management Convention) was eventually adopted by an IMO Diplomatic Conference in February 2004.

EU action

At present there is no direct EU Law on Ballast Water, however Regulation (EU) No 1143/2014 on the prevention and management of the introduction and spread of invasive alien species recognises the BWM Convention as one of the possible management measures for invasive species of concern. The level of Invasive Alien Species and their environmental impact is also one of the many descriptors for assessing Good Environmental Status under the Marine Strategy Framework Directive.

EMSA's role

EMSA has recently completed a 14 point Action programme to help the EU Member States implement the BWM Convention and contribute to the advanced work being undertaken on this issue in the Regional Sea Committees around Europe. The IMO Convention for Control and Management of Ships’ Ballast Water and Sediments is expected to enter into force in the near future. In the meantime EMSA is monitoring the deliberations at IMO on the BWM Convention and its Guidelines.

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