Spud barge Aarsleff Jack III left a nasty pile behind while on an easterly course in the South of Gedser Traffic Separation Scheme, TSS, in the western Baltic Sea. Three hours later a containership, Johanna, made contact with the piles, holing her above the waterline.
In the early afternoon of 18 December 2011, the tug Westsund was towing the barge. During the tow operation one spud pile – barge leg – on the barge came loose, lowered itself, hit the seabed and broke off. Later that afternoon, another spud pile came loose and lowered itself to the seabed, resulting in the barge grounding. After an unsuccessful attempt to repair the jack-up unit holding the spud pile, the second spud pile including a pontoon broke off.
About three hours after the loss of the second spud pile, the container ship Johanna passed the area and collided with one of the spud piles. The spud pile penetrated the hull above the waterline and forecastle deck. The crew did not become aware of the damages until early next morning and Johanna diverted to the port of Karlskrona, Sweden, for repairs.
Says the DMAIB: “It has not been possible to establish for certain what technical circumstances caused the malfunction of the locking pins holding the spud piles, thereby enabling them to come loose and slide out of the hydraulic jack-up unit. However, the wear of the locking pins, the lacking securing of the spud piles and the area and conditions under which the barge was towed are factors that have, with some likelihood, contributed to the breakdown”.
DMAIB has recommended that the Danish Maritime Authority, when further developing the regulation and guidance on barges, focuses on clarifying the role of tug masters in relation to the tow.
It also recommends that the owner of AARSLEFF JACK III, in co-operation with the manufacturers of the barges, supplies the barges having no operational manuals with suitable manuals that cover the subject areas already included in the existing manuals for other barges within their fleet.
Furthermore, it is recommended that the owner, in co-operation with the relevant classification society and manufacturer, reviews the scope and method of the maintenance and check of the jack-up units.
The marine accident report can be read here.