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Photos: Winter Storms Damage Hulk of OS 35 off Gibraltar

wreck removal off Gibraltar
Section of the accommodation block broke away and the hull further split during recent storms (Gibraltar Port Authority photos)

Published Mar 8, 2023 2:10 PM by The Maritime Executive

The Captain of the Port of Gibraltar is reporting that recent winter storms damaged the hulk of bulker OS 35 which sunk last year just offshore after hitting another vessel at the entrance to Gibraltar harbor. The damage to the vessel while not severe may mean that changes will be required to the ongoing salvage operation after the high waves caused damage and a further release of residual amounts of oil from the vessel’s forward oil tanks.

The OS 35 clipped an anchored LNG carrier while it was departing Gibraltar on August 30 and came to rest just off Catalan Bay. The vessel’s bow sunk to the seabed while the stern initially remained afloat but the vessel later fractured and began leaking oil. As bad weather approached last fall, the decision was made to sink the remaining portion of the vessel. Early this year, the salvage efforts began.

Storms passing through the area in late February, however, have further damaged the hulk including causing a small section of accommodation block to break away. The port captain reports that the high waves pounding against the starboard side of the vessel caused the piece to fall away as well as extending the original break in the hull and straining other cracks. A large area of buckling and cracking developed in the area of the number four hold as well as smaller areas of buckling in both the number one and two holds.

 

Starboard section of the accommodation block collapsed during the storm (GPA)

 

“The damage to the vessel’s hull and accommodation block, whilst not ideal, were anticipated and prepared for with the removal of as much oil as possible and the complete stripping of the accommodation,” said John Ghio, the Captain of the Port. “These measures, together with the decision to sink the wreck in a controlled manner and thereby secure it in place, gave the vessel the maximum possible stability to withstand the winter storms as far as possible.”

After the storms, divers did a further inspection of the hull reporting that the storm had driven the bow section an additional 13 feet into the sand while the stern section is down an additional six to seven feet. The heavy swell shifted the sandy bottom around the vessel. They were able to see that all four fuel tanks that made up Tank 1 in the bow section are damaged and the source of additional light sheening around the wreck. The other set of tanks in the stern making up Tank 2 remain undamaged. All the tanks were pumped last fall with only residuals remaining. The storms however also caused tar balls to wash up both on the beach in Gibraltar and across the bay in Spain.

 

Only the bilge keel holds the two sections together (GPA)

 

The divers reported that the two sections of the vessel are now only tenuously held together. The only remaining connection is at the bilge keel. The salvage plan however calls for separating the two sections and lifting them independently.

The port captain said the priority remains the removal of the cargo from the holds of the OS 35. Approximately 600 to 900 tons of the steel bar cargo is being removed daily. Since beginning the removal operation in mid-January, over 11,000 tons of cargo have been lifted from the vessel.

The salvage plan anticipated lost time due to winter storms, so they believe overall they remain on schedule to have the hulk removed before the summer. However, they expect that they may have to “tweak the plan” for the final removal based on the recent damage to the hull and structure.
 

Boom remains in place to catch debris and oil while the cargo removal resumed after the storms (GPA)