Maritime Glossary
Ballast
Also known as: ballast water
Water taken on board a ship to provide stability and maintain safe trim when cargo spaces are empty or partially loaded.
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Full Definition
Ships take seawater into ballast tanks located in the double bottom and wing spaces to control trim, stability, and propeller immersion when cargo is absent. Taking and discharging ballast is routine at every port. Ballast water poses an ecological risk by transporting invasive aquatic species between bioregions; management is regulated under the IMO BWM Convention (2004, in force 2017), which requires ships to treat ballast water with an approved Ballast Water Treatment System (BWTS) before discharge.
Domain Tags
operationsenvironmentengineering