Intercargo has proposed “extended ballast water exchange” be used for bulk carriers fitted with gravity discharged topside tanks, to retain vessel efficiency and avoid substantial modification. In a paper submitted to the International Maritime Organisation’s (IMO) Marine Environment Protection 71 Committee (MEPC), it added that the remaining ballast water should be treated by a BWT system to be fitted on all vessels. The bulk carriers association said retrofitting a ballast water management (BWM) system onto a bulk carrier that uses gravity discharge for the topside tanks would require the removal of the gravity discharge systems and the loss of faster ballasting and deballasting and highly energy efficient systems. New connections between topside tanks may also have significant impacts on stability, it stated. Speaking ahead of the IMO’s MEPC 71 meeting in July, Intercargo stressed that retrofitting would need to overcome major technical challenges in light of the substantial modifications the bulk vessels would require. A significant proportion of the world bulk carrier fleet utilizes the gravity discharge system for the topside ballast water tanks and Intercargo said regulations should avoid marginalising bulk carriers. Intercargo said it welcomed the entry into force of the Ballast Water Management (BWM) Convention in September, but would be reiterating the critical challenges faced by the bulk carrier segment of the industry” to the MEPC 71 Committee.