State-run Shanghai Salvage Co. has sent ships and manpower to lift the Sewol ferry, which sunk off southwest coast of the Republic of Korea (ROK) in April last year.
Two salvage ships, Dali and Huahe, left Shanghai for Jindo Island Wednesday, where the 6,8255-tonne Sewol lies 44 meters deep on the sea bed.
A total of 150 technicians and crewmen will participate in the salvage effort, said Jiang Yan, deputy director of the Shanghai Salvage company.
"It is extremely difficult to lift the ship because it fell on its left side, titling 90 degrees. Poor visibility and unpredictable seawater pose substantial danger to the divers and workers. We have to send the ablest staff, make every preparation needed and take caution," Jiang, who leads the salvage operation, told reporters.
Sewol, carrying 475 people, mostly high-school students, capsized on April 16, 2014, leaving at least 304 people dead. A total of 295 bodies were recovered, but nine remained unaccounted for after divers called off the dangerous search of the sunken vessel last November.
Families and relatives of the deceased had voted for resurfacing the ferry, with some believing the nine missing bodies are still inside Sewol.
The salvage efforts will last about a year, Jiang said. The consortium of Shanghai Salvage, with the ROK company Ocean C&I, beat seven other consortiums to win the bid in early August.
They plan to use a frame built with steel beams on the sea floor instead of drilling holes into its side.
"Using steel structure to uphold the ship is the best way to keep the ship whole," Jiang said.
Shanghai Salvage had hoisted the Eastern Star, a Chinese ship which sunk in the Yangtze River on June 1.