Green Shipping | Part 4: Spotlight: ballast water

November 2020 | “Green Shipping” not only concerns the avoidance of pollutant emissions. Wastewater is also a major issue in shipping – not only what is consumed on board, but also special areas such as so-called ballast water. This is needed to ensure the stability of the ship in every situation. This special type is what our current contribution to environmental protection in shipping is all about. 

For stability reasons, most ships have to absorb ballast water when unloading the cargo and release it when loading. Tankers and bulk carriers have a particularly large volume of ballast water. More than 10 billion tons of ballast water are transported worldwide every year. Since this is seawater, animals, plants and microorganisms are also affected – every day more than 3,000 different types of ballast water are transported between ports around the world. The diagram below illustrates the procedure:

Grafik Ballastwasser


The carry-over of organisms via ballast water massively impairs biological diversity and damages it through so-called invaders. A well-known example is the Chinese woolly hand crab, which has already spread in all major river systems in Europe and displaced native species because it has no natural enemies.

In addition, untreated ballast water can also pose a health hazard. For this reason, special rules have been in force for some years now to deal with this problem.

What legal regulations exist in connection with ballast water?

  • Global regulation of the International Maritime Organization (IMO)

The International Convention for the Control and Management of Ship’s Ballastwater and Sediments (BWMC) was introduced on September 8, 2017. Since then, newbuildings with keel laying must be equipped with an IMO-approved ballast water treatment system on delivery. For all other ships, a ballast water treatment system must generally be retrofitted at the first class renewal/docking (formally: at the first renewal of the IOPP certificate) after the deadline. This class renewal is due every five years. The existing fleet is thus subject to a retrofitting obligation, which will be completed for the world fleet in September 2024.

  • Special regulation for the USA

A special regulation applies for the USA: 

Newbuildings delivered since December 2013 must have a ballast water treatment system (“type approved”) approved by the US Coast Guard. All other ships must install a corresponding system at the first scheduled docking after January 1, 2016. Due to the lack of availability of U.S. Coast Guard certified systems, extensions were initially granted. In the medium term, however, ships will no longer be allowed to call at the USA without a ballast water treatment system approved by the Coast Guard.

What technical solutions are available for implementation?

There are various mechanical, physical and chemical processes. On the one hand, they aim to filter out the organisms, on the other hand they ensure that remaining organisms can no longer reproduce. Only the USA goes one step further and demands their killing. 

The most common systems are those that either irradiate the ballast water with UV light or treat the ballast water by electrolysis. This is usually done in combination with mechanical filters. 

What are the costs of retrofitting?

For the – unavoidable – re-equipment of a cell phone size bulker with a ballast water treatment system (BWTS), total costs of at least approx. 500,000 USD are incurred. They include costs for planning, installation, supply and discharge lines and other modifications to the ship. 

However, the conversion can also become considerably more expensive if, for example, the space on board or the existing capacity of the auxiliary machinery is not sufficient to operate the BWTS. 

Is the high cost worth it at all?

Especially for older ships, which due to their size, energy efficiency, equipment, etc. already have considerable competitive disadvantages compared to modern tonnage, the question of the cost-effectiveness of such expensive measures does indeed arise. With a total of around 3,800 Handysize bulkers, we are talking about almost 700 ships that will have to be re-equipped in the coming years. But without them, they cannot be used any further. We assume that many shipping companies would rather have these ships scrapped than invest in retrofitting.

How is Vogemann dealing with these requirements?

In all newbuildings for which Vogemann has signed construction contracts since 2014, electrolysis technology is already being installed at the shipyard. For the existing tonnage of cell phone size bulkers, electrolysis ballast water treatment plants will be installed at the first major class docking after 2018. In two tankers, systems with UV technology were retrofitted.

Would you like to learn more about environmental protection measures in shipping and how the Vogemann shipping company deals with them? Click here to get to the introduction of our series. Here, here and here we take a closer look at other pollutant emissions and show how the Green Ship Token paves the way to more sustainability in shipping.