The need and extent of exchange of ballast water will be decided by the requirements of the next port(s) of arrival. It is important to refer to the Ballast Water Management Plan for this purpose. The ballast water exchange must be done to satisfy the more stringent of the requirements.
Some Port states may notify the vessel where the ships should not uptake ballast water due to known conditions which may result in the uptake of harmful aquatic organisms and pathogens or are near sewage outfalls etc. The Master shall receive the co-ordinates of such areas.
The uptake of ballast water should be minimized and avoided in areas and situations :
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areas identified by the Port state (port state may inform local agents and / or the ships of areas where the uptake of ballast water should be minimized or avoided)
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in darkness when bottom-dwelling organisms may rise up
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in a very shallow waters
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if water is stirred up by propellers or dredging
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near sewage outfalls
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areas where toxic algae blooms are occurring
If ballast has been taken in under such circumstances, the Master shall ensure that this ballast is exchanged as far away from nearest land as possible and in as deep waters as possible.
There are three methods of carrying out ballast water exchange:
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Sequential method: ballast tanks are pumped out and then refilled with water
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Flow-through method: ballast tanks are over-flowed by pumping in additional water to dilute the original water
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Dilution method: water is pumped in from one end and removed from the other end.
The ship is required to carry out exchange of ballast as follows:
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1) When using the Sequential method , the ballast water in the tanks should be pumped out till the pumps lose suction. Maximum ballast water must be exchanged, but in no case shall the efficiency be less than 95 per cent volumetric exchange of ballast water in each tank. In cases where 95% efficiency is not met, stripping pumps should be used to meet the criteria. When using the Flow Through method or the Dilution method, replace of ballast water by at least three times the volume of each ballast tank.
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2) In deep waters where the depth is at least 200 meters.
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3) At a distance of at least 200 Nautical Miles away from nearest land.
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4) If the ship is unable to conduct ballast water exchange as required by above requirement, such ballast water exchange shall be conducted as far away from nearest land as possible, but in all cases at least 50 nautical miles away from the nearest land and in as deep waters as possible and at least 200 meters in depth.
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5) If above requirements cannot be met, the Master shall convey the ship’s inability to carry out ballast water exchange to the Port State. Certain Port State authorities may allow the ship to conduct ballast water exchange in designated areas under its jurisdiction under prescribed conditions. Under such permission, the Master may carry out the required ballast water exchange.
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6) If the ship is returning to the region of the ballast origin and the ballast is not mixed with ballast of other origin the Master must contact the Port State authorities prior conducting the deballasting operation, in case he does not intend to carry out the ballast water exchange and obtain permission for discharge of the un-exchanged ballast water within the regulated limits.
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7) All available pumps and lines must be used for the ballast water exchange to ensure that these are properly flushed of their previous contents. The lines and pumps should not be drained out.
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8) If local requirements of a Port State require the ship to have a higher standard of ballast water exchange, the Master shall ensure the relevant requirements are complied with
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9) Reference shall be made to Ballast Water Management Plan for Port state requirements. However, the Coastal State should be contacted if necessary for the specific Ballast Water Discharge requirement and reporting prior to the vessel’s arrival in the Port State’s waters. The Master will thus obtain all information in good time and prepare the vessel accordingly. If the Coastal State has specific procedures for ballast water discharge, the following action shall be taken:
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- a) Follow agreed procedures.
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- b) Contact the ship’s agent and owners/managers/operators to ascertain the latest information on ballast discharge in the port state.
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- c) Ensure that the plan for the required actions is appropriate with regard to its effectiveness and safety of the ship and her staff.
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- d) Maintain the relevant records.
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10) All lines containing sea water (e.g. cooling lines, fire lines etc.) must be re-circulated with mid ocean water to replace the water in the lines.
The ship shall not be required to comply with the ballast water exchange requirements if the decides that such exchange would threaten the safety and/or stability of the ship, the people on board the ship or her cargo. Such decisions shall be taken after notification to Ship Owner/Operator and in consultation with the Ship Superintendent. An appropriate entry shall be made in the Ballast Water Record Book stating the reasons for such non-compliance and also in the ship’s log book. The Port State authorities shall be notified accordingly.
The following to be considered prior making the decision:
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Weather conditions.
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Any special design or feature of the ship.
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Machinery failure or inappropriate performance of the machinery.
Where due to circumstances mentioned above, ballast water exchange could not be carried out, ballast water may need to be discharged to a shore reception facility.
