What Is Ballast Water?


You probably didn’t know that cruise ships, large tankers, and cargos take up some amount of water to support their buoyancy. The water kept in the hull of boats is popularly regarded as Ballast Water. But, what exactly is ballast water? What’s its importance, and how does it affect the environment? Keep reading to find out.

Definition Of Ballast Water

You may ask yourself, what is ballast water? To put it simply, ballast water is the freshwater or saltwater stored in a ship’s hull to support the stability and movement of the marine vessels during exercise. A certain amount of water is taken into the hull at the departure port and emptied at the destination. This water is often filled with different organisms such as microbes, invertebrates, eggs, larvae, and bacteria. Ballast water is responsible for most of the transfer of marine species around the world’s oceans.

Why Is It Important?

Ballast water is stored onboard to manage the ship’s weight. Ballast water will also compensate for changes in the importance of the ship’s cargo and ensure that it can navigate better in rough tides. Often, the vessel may carry about 30 – 50% of its total cargo in ballast. Depending on the ship’s size, this could range from a few hundred to millions of gallons.

What Is The Environmental Impact Of Ballast Water?

According to history, the foreign aquatic bodies and invasive species transferred due to ballast have severely damaged water bodies. For instance, the invasion of zebra mussels in freshwater can stifle the growth of native fish species in that region. The round goby would alter the food chain in a new habitat. This alteration could reduce the population of native species.


And that’s all on the meaning and importance of ballast water. By studying the environmental impact of Ballast water, we can reduce damage to the environment and improve natural selection in water bodies.

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