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The Seaspan 240 is a 12 300 ton capacity flat deck bulk carrier barge 375'x 75'x 25' built at Yarrows Shipbuilding in 1966for Island Tug and Barge Co. Ltd. Since launching, the barge has been in the bulk trade on the North American Pacific Coast. On July 16,1996 while under tow, fily laden with a cargo of limestone, the barge capsized off the headland at Port Townsend, Washington. After the incident the capsized barge was towed to Vancouver Shipyards Co. Ltd. in North Vancouver, BC, where the vessel was righted. This paper outlines the planning, preparation for, and results of, the righting salvage. The very successful salvage operation carried out on August 14, 1996 represents a culmination of learned knowledge from other barge turnings over the past few years by Seaspan's marine and technical staff.
PHASE 1-DISCOVERY
Upon its delivery to the shipyard the vessel was inverted, slightly down by the head, and listing to starboard. The first order of business was the securing and assessment of the vessel's condition. The vessel was held alongside by tugs until mooring lugs were welded to the side shell and shore lines tied on. Then all of the hull compartments were sounded through the docking plugs to determine which void spaces had been compromised from the capsizing. In order to prevent the vessel from taking on further amounts of water the damaged compartments were fitted with compressed air connections at the docking plugs and pressurised to 2 psi. It was found that the number 1 and number 7 port hull voids and the forepeak held the most water, and with air pressure applied to these spaces the list was removed, as was most of the bow trim. After these obviously damaged tanks were pressurized and blown out, the other tanks were tested with air pressure to ascertain that their integrity had not been compromised internally or externally. For a successful salvage this information is of primary importance in the formulation of a righting plan.
Once the tank check was complete and the barge's trim condition stabilized, divers were brought in to visually survey the vessel for damage. From their survey, it was found that the barge's port box wall had broken in several places and set down...