816 - 03/12 - Dangers of pressing up ballast tanks - Worldwide
In a recent case an entered vessel pressed up its ballast tanks in order to optimise trim and to satisfy mandatory stability criteria. The operation resulted in the unexpected flooding of a cargo hold causing extensive damage to cargo.
An entered containership was carrying out ballast exchange operations mid voyage and pressed up one set of double bottom ballast tanks. On arrival it was observed that one of her holds had significant water inside and considerable damage to bottom stow cargo.
The vessel had recently opened up several manhole covers for routine inspection of her ballast tanks.
After the incident it was noted that the high level bilge alarms in the hold were not functioning.
Whilst investigations are still continuing into this particular case it maybe timely to remind Members that poorly secured manhole covers are still a frequent cause of water ingress into holds, many, but not all, arising after drydocking where shore staff have not secured covers properly.
- If double bottom manhole covers are removed for whatever purpose it is recommended a note be made of where and when, this not only acts as an aide memoire but also helps in defending claims should water ingress occur
- Good maintenance should also be in place, the manhole covers/gasket arrangement and like should be routinely checked, if not already included as part of the routine inspection / maintenance programme associated with the ship’s ballast tanks
- Hold high level bilge alarms should be tested on a regular basis, logged and defects, if any, rectified immediately.
Source of Information:
Thomas Miller (Americas)
San Francisco, USA