In the 2020’s Safety Digest, the UK MAIB refers to a container vessel that listed heavily to starboard, when the chief engineer decided to pump more water into the starboard ballast tanks to level up tank volumes. commenting that ballast operations should be planned to avoid any accident.
A container vessel had finished its container loading operations and had began preparations to sail; The weather was fine with a gentle breeze. When the chief officer observed port and starboard ballast tanks’ contents from the tank capacity gauges on the operating panel, decided to pump additional water into the starboard ballast tanks to level up tank volumes.
As the volume of water in the starboard tanks increased, the vessel started to list heavily to starboard. As the situation deteriorated, all the crew evacuated ashore.
The managing company, the master and the port authority, proceeded to an assessment, and resulted that it was safe for the crew to return on board and recover the situation by pumping out the ballast water from the starboard tanks.
Following the incident, manual sounding were conducted, that showed that one of the port ballast tanks’ gauges had been reading full when the tank was actually empty, and the fault was almost certainly an airlock in the gauge system.
Lessons Learned
It is highlighted that
Ballasting operations should be planned, and maintaining an accurate picture of the state of the ballast system is critical for the safety and stability of the vessel.
As the vessel was upright, there was no reason to add water to one side. When the vessel started to list, it would have been readily apparent that the ballasting was the problem, and this should have been stopped immediately.
Ballast system gauges are prone to inaccurate readings, so tanks should be sounded regularly with the levels recorded in the ballast logbook. This information can then be compared with gauges to
check for discrepancies.
