IMO REGULATIONS ON THE CONTROL AND MANAGEMENT OF SHIPS' BALLAST WATER AND SEDIMENTS (BWM)
The international maritime organization has initiated the International Convention for the Control and Management of Ships' Ballast Water and Sediments. The Ballast Water Management Convention requires:
The Convention stipulates two standards for discharged ballast water. The D-1 standard covers ballast water exchange while the D-2 standard covers ballast water treatment To comply with BWM Regulation D-1 and / or D-2, you must develop a Ballast Water Management Plan and submit it for approval. The Plan must demonstrate how you will achieve:D-1 Standard - Ballast Water Exchange
With a goal to achieve volumetric exchange of ballast water of up to 95% of the ballast water capacity, this standard does usually not require modifications to the ship’s existing equipment. Methods used to achieve the goal include: flow-through (pumping to overflow); dilution (ballasts filled through the top allow discharge from the bottom); and sequential (each ballast is emptied and refilled).D-2 Standard - Ballast Water Performance
Performance as it involves modifying ship design to install an approved Ballast Water Management System (BWMS). The treatment system is to ensure that discharge water meets defined performance standards, with strict limits on concentrations of viable organisms and microbes. It comprises ballast water treatment equipment, all associated control equipment, monitoring equipment and sampling facilities. The vessel must also carry on board a ballast water record book.
US legislation requires the Ballast Water Treatment System (BWTS) to be approved by the US Coast Guard.