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Ballast water management - the control of harmful invasive species


​​​​​Ballast Water 2016_NEW_thinner_.jpg

Ship discharging ballast water

Ballast water may be taken onboard by ships for stability and can contain thousands of aquatic or marine microbes, plants and animals, which are then carried across the globe. Untreated ballast water released at the ship’s destination could potentially introduce a new invasive marine species.  Hundreds of such invasions have already taken place, sometimes with devastating consequences for the local ecosystem. 
The International Convention for the Control and Management of Ships' Ballast Water and Sediments  (BWM Convention​) was adopted in 2004 to introduce global regulations to control the transfer of potentially invasive species. Once the treaty enters into force, ballast water will need to be treated before it is released into a new location, so that any microorganisms or small marine species are killed off. 
The BWM Convention will enter into force on 8 September 2017.

Read more here​ 

The BWM Convention will enter into force on 8 September 2017.  

BWM treaty requirements
Under the Convention, all ships in international traffic are required to manage their ballast water and sediments to a certain standard, according to a ship-specific ballast water management plan. All ships will also have to carry a ballast water record book and an international ballast water management certificate. The ballast water management standards will be phased in over a period of time. As an intermediate solution, ships should exchange ballast water mid-ocean. However, eventually most ships will need to install an on-board ballast water treatment system.
Click here​ to read more about the requirements.  
Invasive species - An example....

The North American comb jelly Mnemiopsis leidyi​ has travelled in ships' ballast water from the eastern seaboard of the Americas to the Black, Azov and Caspian Seas. It depletes zooplankton stocks; altering food web and ecosystem function. The species has contributed significantly to collapse of Black and Azov Sea fisheries in 1990s, with massive economic and social impact. It now threatens to have a similar impact in the Caspian Sea. There are many other examples of invasive species, some are listed here​
Approval of BWM systems 
The BWM Convention requires that ballast water management systems used, to comply with the Convention, must be approved by the Administration taking into account the Guidelines for approval of ballast water management systems (G8). 
Read more here


Ballast water sampling on a ship

Capacity building - GloBallast
IMO is executing the GEF-UNDP-IMO GloBallast Partnerships Programme (2008-2016) to sustain the global momentum in tackling the ballast water problem and to catalyse innovative global partnerships to develop solutions. The GloBallast Partnerships website is​​​.
The GloBallast Partnerships project has developed two training courses: an introductory training for personnel having different skills, knowledge and experiences in ballast water related issues, which provides a common set of knowledge and skills to all participants to enable them to take appropriate action in their various capacities with a view towards promoting uniform implementation of the BWM Convention; and a multi-module course directed to legal experts and administrators (GloBallast training course on the legal implementation of the BWM Convention). Click here for more information.