The minimum levels of acceptance for the International Maritime Organization's Ballast Water Convention have now been achieved and the convention has been ratified. Designed to prevent invasive aquatic species carried in the ballast water of ships being discharged into the sea where they could harm local species, the convention will enter into force on 8 September, 2017.

Finland is the latest country to sign up for accession, bringing the number of countries to 52, which is over and above the minimum of 30 IMO member states required by the convention. However, ratification also required that the signees represent 35 per cent of the world's registered gross tonnage. This proved a stumbling block, but Finland's acceptance takes the percentage to just above the minimum level required.

Because of their operational profile, superyachts do not usually require a water ballast system, but some do have seawater ballast; for example, conversions from commercial vessels or large sailing yachts to improve upwind angles. Others use fresh water from shoreside sources, or water produced on board using reverse osmosis (RO) systems. Technically, however, this is still treated as ballast water by the convention (ironically, this means there is nothing to stop a yacht being washed down using the same water from its fresh or technical water tanks).

As of 8 September, 2017, every yacht to which the convention applies must implement a Ballast Water Management Plan (BWP) that has been approved by its administration. It is yacht specific and must contain details of the procedures necessary to comply with the convention's requirements. Yachts will also be required to keep a Ballast Water Record Book that must be maintained on board the vessel for at least two years after the last entry, and thereafter retained for a further three years.

Compliant yachts of 400gt or over will need to be surveyed and issued with a valid International Ballast Water Management Certificate (IBWMC), issued by flag or other organisations such as classification societies. For yachts under 400gt, administrations will establish appropriate measures to ensure they comply with the applicable provisions of the convention.

More than a decade has passed between approval and ratification of the convention, but marine companies have been working to develop approved ballast water treatment systems. The Aquarius range by Wärtsilä (pictured), for example, uses automatic back-washing screen type filters and ultra-violet light (UV) or electro-chlorination as methods of disinfection.

The convention undoubtedly represents additional book keeping for captains or management agencies and extra expense for owners, but it will now come into force and have an impact on those superyachts that use ballast water in any way. Yachts currently in build should either comply with the standards required, or at least make preparations for retro-fitting a treatment system in the near future. Those already in operation should also look into the equipment and systems necessary to comply with the convention.  

Use these links for additional information on ballast water management from the IMO and Lloyd's Register


Profile links

International Maritime Organization (IMO)

Lloyd''s Register EMEA

Wartsila Propulsion