Shipowners continue to face major challenges with the impending ratification of the International Maritime Organization’s (IMO) Ballast Water Management Convention (BWMC). As BWMC edges towards its required ratification numbers and comes into force, it will have significant impact on merchant shipping and in particular owners operating in regional and coastal trades, the conference, which is part of the Asia Pacific Maritime (APM) event taking place at Marina Bay Sands, heard.