Ship Operations Dictionary Entry
Ballast Water
"Fresh or saltwater held in tanks and cargo holds of a ship to increase draft, change trim, and regulate stability."
Purpose
Ballast Water is essential for safe ship operations. When a ship unloads cargo, it becomes lighter and floats higher in the water. To ensure the propeller is submerged and the ship is stable against waves, water is pumped into dedicated ballast tanks.
Environmental Impact
Ballast water taken in one port and discharged in another can introduce Invasive Aquatic Species (e.g., Zebra Mussels) that devastate local ecosystems.
Regulation
The IMO Ballast Water Management Convention (BWMC) requires ships to treat ballast water (using UV or Chemical systems) before discharge to remove harmful organisms.
Related Terms
DraftStabilityBallast Water Management Convention