In this blog post, we’ll analyze the impact of ballast water on the marine ecosystem, explore the problems caused by the introduction of invasive species, and examine ballast water treatment systems (BWTS) designed to address these issues.
Ms. K, a Korean woman, enjoys eating Chilean grapes that are high in sugar content and can be eaten with the skin on. Today, as always, she orders Chilean grapes. Every morning, Ms. K eats fresh, sweet Chilean grapes for breakfast to stay healthy. She has never thought about how far these grapes travel or the process they go through to reach her; she is simply satisfied that they always arrive fresh.
At the Chilean grape processing plant that received the order, the grapes are loaded into a container ship bound for Korea. These grapes are carefully packaged and meticulously managed to maintain their freshness during the long voyage to Ms. K’s dining table. Countless people collaborate throughout this process, striving to ensure the grapes maintain the highest quality until the moment they reach Ms. K.
A container ship that has traveled halfway around the globe and docked at Busan Port. However, the fish living in the waters off Busan are utterly astonished. This is because a massive number of exotic fish—specifically, Chilean fish—have appeared, something they have never seen before in their lives. To the fish in the waters off Busan, this situation is like a completely new world they knew nothing about suddenly appearing. The moment they encounter these unfamiliar Chilean fish, the ecosystem loses its delicate balance, and signs of change begin to emerge.
Did you know that when you order Chilean grapes, Chilean fish come along with them? This fact may seem unfamiliar to many people, but it is actually happening every day. How did these fish end up in Korea? Before explaining the reason, readers need to understand what ballast water is. For a ship to float and move on the ocean, the depth to which it is submerged must be maintained at an appropriate level. To achieve this, the ship takes on a certain amount of seawater. In other words, the ship maintains its balance by repeatedly filling and releasing seawater into specific tanks. The seawater used to maintain this balance is called ballast water.
A container ship loaded with grapes from Chile also inevitably sets sail carrying this ballast water—that is, seawater. However, this seawater contains various species of Chilean marine life. Not only fish, but also small plankton and microscopic marine organisms are carried along. These organisms are generally very small creatures that people rarely notice, but their migration routes are global. At the Port of Busan, container ships discharge the ballast water used during their long-distance voyages and take on new ballast water. It is through this process that fish from Chile have appeared in the waters off Busan, alongside Korean fish. As a result, the ecosystem off the coast of Busan faces a new challenge.
The British shipping analysis firm Clarksons has projected global container traffic for 2024 at 2.08 million TEU. You may be seeing the term “TEU” for the first time. A TEU refers to a single container measuring 20 feet in length, 8 feet in height, and 8 feet in width. While this is just one container, it serves as a reminder that millions of containers departing from ports around the world are transported in the same manner. In other words, it shows that an enormous volume of cargo is being transported globally via container ships. During this transport process, a massive number of fish are also being carried to all corners of the globe via ballast water. It is no longer surprising to find fish originating from Chile in Busan, or conversely, to discover Korean marine life on other continents.
This dispersal of fish across the globe causes catastrophic damage to marine ecosystems. This is similar to the phenomenon where invasive species like the American bullfrog and bluegill threaten Korea’s native ecosystems. The discovery of North American jellyfish in the North Sea, the colonization of the Great Lakes by European mussels, and the presence of crabs native to the Mediterranean in Australia or South America are all due to ballast water. If this phenomenon continues, biodiversity will disappear, and the disruption of native ecosystems will worsen, accelerating the chaos in marine ecosystems. As a result, marine resources in specific regions may decline rapidly, or native species may face the risk of complete extinction. Ultimately, these problems will directly affect people’s lives, as changes in marine ecosystems can have a negative impact on fisheries, tourism, and the overall marine economy.
The solution to these problems is the BWTS (Ballast Water Treatment System), which is the keyword of this blog post. The basic concept of this treatment system is to keep ballast water clean by preventing or eliminating the organisms in it using physical and chemical methods. It primarily utilizes filters and disinfectants such as ultraviolet light and ozone. Currently, the International Maritime Organization (IMO) signed the “Ballast Water Management Convention” in 2004 and has mandated that all ships with a ballast tank capacity exceeding 5,000 cubic meters must be equipped with a BWTS starting in 2016. The introduction of this system is expected to contribute not only to the protection of marine ecosystems but also to the sustainable development of the shipping industry.
Installing a BWTS on a single ship costs approximately 10 to 15 billion won. Installing them on all 68,190 international container ships worldwide would require a staggering 80 trillion won. Although the cost is enormous, in the long term, this is considered an essential investment for protecting the marine ecosystem and ensuring a sustainable shipping industry. To secure a foothold in this massive market, all shipbuilders are working feverishly, accelerating the development of new technologies and the establishment of efficient systems. These technological advancements will ultimately contribute to achieving the dual goals of protecting the marine environment and fostering economic growth.
