“Invasive marine species are one of the four greatest threats to the world’s oceans. Unlike other forms of marine pollution, such as oil spills, where ameliorative action can be taken and from which the environment will eventually recover, the impacts of invasive marine species are most often irreversible.”
(source: International Maritime Organisation IMO)
The IMO developed and adopted “The International Convention for the control and management of ships ballast water and sediments, 2004” (Ballast Water Management Convention) with the aim of protecting the marine environment from the transfer of harmful aquatic organisms in ballast water carried by ships.
According to IMO estimates, ships carry some 3 billion tons to 5 billion tons of ballast water globally each year.
The convention entered into force 8 September 2017, 12 months after 30 countries representing a combined total gross tonnage of more than 35% of the world’s merchant fleet had ratified it. With the ratification of Finland on 8 September 2016, 52 countries representing a combined tonnage of 35.1441% of the world’s merchant fleet had ratified the convention. This means all ships must have a ballast water management plan, a ballast water record book and an International Ballast Water Management Certificate.
During MEPC 72 amendments to the convention's D2 standard were adopted, meaning all ships must meet the D2 standard by 2024 latest. Currently 74 countries have signed the convention, representing over 75% of world merchant shipping tonnage.
The implementation dates for vessels after 8 September 2017 based on the amended B-3 regulations approved during MEPC 71 is as follows:
Vessels constructed on or after 8 September 2017 need to comply to the D-2 standard per 8 September 2017.
Vessels constructed before 8 September 2017 that require an International Oil Polution Prevention (IOPP) certificate need to comply to the D-2 standard as follows:
I. By the first IOPP renewal after 8 September 2017 and in case a prior renewal survey has been completed between 8 September 2014 and 8 September 2017;
II. By the first IOPP renewal in case this renewal place after 8 September 2019;
III. By the second IOPP renewal in case the first IOPP renewal takes place between 8 September 2017 and 8 September 2019 but the previous IOPP was done before 8 September 2014.
Despite the varying compliance dates for ships, all ships must meet the D-2 standard by 8 September 2024 latest. Untill complying to the D-2 standard all ships must meet the D-1 Ballast Water exchange standard.
The convention stipulates two standards for discharged Ballast Water:
D-1: Compliance with Ballast Water exchange standard:
• Ships performing a Ballast Water exchange shall do so with an efficiency of 95% volumetric exchange of Ballast Water.
• For ships exchanging Ballast Water by the “Pumping through method”, pumping through three times the volume of each Ballast Water Tank shall be considered to meet the standard described. Pumping through less then three times the volume may be accepted provided the ship can demonstrate that at least 95% volumetric exchange is met.
D-2: Compliance with the Ballast Water performance standard:
• The Ballast Water performance standard requires minimum post-treatment concentrations of organisms both dependent on size as well as on specific types of organisms .
Table 1. Ballast Water performance standard
Important Note: The Ballast Water Management Convention has been ratified 8 September 2016 and will enter into force 8 September 2017.
Once the Ballast Water Management Convention has entered into force, all ships of 400 GRT and above will be required to have on board:
• A ships specific approved Ballast Water Management Plan approved by the administration.
• A ballast Water record book.
• An international Ballast Water Management Certificate.
• An approved Ballast Water Treatment system according to the implementation schedule above.
Note: Ships below 400 GRT will be subject to national survey and certification regimes.