The UK Marine Accident Investigation Branch (MAIB) has published its report on the capsizing of the prawn trawler Odyssey in the North Sea approximately 133 nautical miles southeast of Peterhead, Scotland, on October 29, 2024.
On the said date, Odyssey capsized and sank in the North Sea. All six crewmembers abandoned ship to a liferaft and were rescued uninjured.
The accident occurred after high-capacity deck wash pumps were left running unattended, while the crew recovered the fishing gear, discharging water onto the vessel’s weathertight shelter deck.
The MAIB said it is likely that a blocked tonnage valve prevented the water from escaping, resulting in rapid flooding and a catastrophic loss of stability.
The MAIB found that Odyssey's shelter deck had limited drainage by design, leaving it vulnerable to water build-up when the drainage became compromised. Also, the crew initially mistook the developing list to be normal movement associated with recovering the fishing gear.
There was a lack of guidance in relation to flooding risk from deck wash pumps and the danger had not been addressed in the vessel’s risk assessments. Fortunately, emergency preparedness helped the crew successfully abandon the vessel.
Recommendations have been made to the Maritime and Coastguard Agency (MCA) to update Merchant Shipping Notice 1872 (F) Amendment 1 to ensure that existing vessels without the independent pumping capability outlined in 4.3.2.1 (iii) have additional measures in place to adequately address the risk of water accumulation on weathertight shelter decks due to blocked, seized, or shut tonnage valves or other water freeing arrangements, and to update its Marine Survey Instructions for the Guidance of Surveyors and relevant aide-memoires.
The MCA has also been recommended to provide guidance on the additional measures that can be implemented to adequately address the risk of water accumulation on weathertight shelter decks caused by blocked, seized, or shut tonnage valves or other water freeing arrangements.
