When Manson crews hoisted the sunken 49-ft ALEUTIAN ISLE fishing boat to the surface, there was a collective sigh of relief—but Project Engineer Kurt Dever knew the job was far from done. “With everything that happened up to this point on this salvage, we still had to pull off a few major moves before we could officially call the project complete,” Kurt says.
In mid-August 2022, the ALEUTIAN ISLE sank in the Salish Sea, just west of the San Juan Islands off the coast of Washington. A team made up of the United States Coast Guard (USCG) and Global Diving and Salvage (Global) responded to the initial search and rescue incident for the vessel. All members aboard were located and rescued safely, but the boat—with a fuel capacity of 4,000 gallons—had sunk to a depth of 250 ft. while carrying 2,500 gallons of diesel fuel. An oil sheen stretching out nearly two miles from the sunken vessel had quickly formed and the leaking needed to be controlled. The U.S. Department of Ecology, the USCG, and other supporting agencies conducted overflights to monitor the area and ensure the safety of marine animals that frequent the San Juan Islands, including the endangered southern resident orcas. Global’s dive crews found the area challenging to work in due to the depth of the vessel would require special equipment and gas mixture to allow the divers to reach the boat. After Manson was contracted by Global, Kurt along with the Seattle Yard crew and Derrick Barge 24 (DB24) crew assisted Global to load the required equipment and specialized gas cylinders onto the DB24 to be towed to the jobsite.
“That particular area where the ALEUTIAN ISLE sank proved challenging for divers because of strong currents in the area—as well as the limited dive time due to the depth of the dive and unpredictability of slack tide,” Kurt explains. “The slack tide times did not match up with what was shown on the tide charts, and divers only had approximately 40 minutes of dive time on the vessel each day before having to resurface and enter their decompression chamber.”
Despite these difficulties, divers successfully secured the vessel and removed extra fishing nets that would disturb the hoisting of the boat.
Due to the depth, this salvage called for a unique rigging process to recover the ALEUTIAN ISLE from the bottom of the sea floor. The DB24 crew worked with Global to hook up the bow and stern connection points to the vessel. Once all the connections to the vessel were made, crews began the hoist, which took approximately three hours.
Once the ALEUTIAN ISLE made it just above the surface, Global began defueling and dewatering to reduce the boat’s weight.
“Global had estimated the boat would weigh around 80 tons after defueling and dewatering,” Kurt says. “Even after defueling and dewatering as much as they safely could, they could not get the weight under 100 tons.” The rigging on the DB24 was approved to hoist up to 100 tons, but because of the vessel’s excess weight, Kurt and the DB24 crew called an all-stop, reassessing their next steps to avoid compromising the wire slings. Holding the vessel in place with the crane’s hook off the working end of the barge, the crew secured the vessel in place for the night using air tugger cables and tag lines until a new plan could be established.
Looking to find a fast, safe, and efficient solution, the Manson crew collaborated with Global, the Dept. of Ecology, and the USCG to find a better way to hoist the ALEUTIAN ISLE completely out of the water. With previous troubles arising from the strong currents, limited dive windows, and weather conditions, all parties agreed that transporting the vessel to a shallower, calmer area would be the safest and most reliable option. The DB24 crew pulled its anchors and mobilized—with the vessel still on the hook—just north to Mosquito Bay, mooring the derrick barge next to the M64 barge being stored on a buoy.
“The current and water depth within Mosquito Bay was way more manageable, and the location was partially protected by land,” Kurt says. “Global was able to continue defueling and dewatering the boat while we prepared to switch out the rigging configuration to hoist up to 150 tons.”
Once the additional fuel was removed, the vessel was re-sunk (under control) to the sea floor and re-rigged using larger wire slings. The crane then lifted the boat up and now completely out of the water, and set and secured it onto the Manson 64 barge. Before the crew brought the vessel back to Manson’s Seattle Yard, the USCG inspected the ALEUTIAN ISLE to ensure it could be safely transported. On a weekend in mid-September, the DB24 and crew, along with the Manson 64 barge and it’s new cargo, arrived back at the Seattle Yard. Manson worked with the Dept. of Ecology to maintain, clean, and prepare the vessel for eventual transportation to the Seattle Iron & Metal further up the Duwamish River for scrapping.
“We normally don’t perform salvages at these depths, so this vessel recovery was a first-time for Manson,” says Superintendent Gordon Hill. “We have a bunch of hard-working and talented individuals on the DB24 who helped get things done.”
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