Remotely operated underwater vehicles will be used to confirm locations and assess the condition of shipping containers lost from the YM Efficiency in June in a bid to determine whether they are recoverable.
Concerned with the lack of progress ship owner Yang Ming and its insurers, Aus Ship, has had in locating the remaining containers that went overboard the cargo ship, the Australian Maritime Safety Authority has employed its own contractor, Brisbane-based salvaging company Subsea, to carry out the underwater search.
“This operation will not be without cost, which AMSA has advised Yang Ming and their insurers that we will be seeking to recover,” AMSA chief Mick Kinley said.
A total of 81 containers were lost from the YM Efficiency in rough weather in the early hours of June 1.
An initial sub-sea search carried out in July located 37 “probable containers”.
Poor weather and sea conditions hampered further search operations until October when sonar technology was used to scan some 200 nautical miles of the seabed between Stockton Beach and Morna Point.
This search returned approximately 40 sonar ‘targets’ which Aus Ship said are likely the location of all the containers except for two which washed ashore after the accident.
Because of the way the containers were attached together on the ship, Aus Ship said it is likely that each target has multiple containers.
Now Subsea, contracted by AMSA, will carry out an underwater search using ROUVs to provide imagery of the containers and any other debris that has been identified by the surveys so far.
“We’ve used a side scanning sonar to map the sea floor and pinpoint the locations of what we believe to be as many as 37 containers,” Subsea managing director Ed Korber said.
“The next phase is to send the ROUVs down to identify what these targets are, confirm whether they are containers, read serial numbers and to take photos and video of them that can be used to asses their condition.
“This will give us the highest degree of confidence that what we think we are seeing down there is what is actually there.”
At the location of the sonar targets, observational class ROUVs connected to a fibre optic tether will be lowered to the sea floor.
A pilot, on a boat above, can remotely navigate the unit to get within a “few metres” of each container to read serial numbers, take photos and record video.
These images will allow salvage experts to assess whether the containers can be brought to the surface safely and without causing further damage to the environment.
Mr Kinley said while AMSA would have preferred that Yang Ming or Aus Ship had taken further action in the search and recovery of the containers, the environmental concerns and impact on the commercial fishing industry created by the submerged containers forced them to act.
“The presence of these containers in the valuable fishing grounds off Newcastle presents an unacceptable risk to local fishers,” Mr Kinley said.
“The dangers of hooking up on debris has understandably led to many local trawlers avoiding these valuable areas which not only impacts their livelihood but also has knock-on effects for the local industry.
“We look forward to meaningful cooperation and action from Yang Ming and their insurers to deal with both the economic loss being suffered by the fishing industry and the removal of the hazard created by the loss of the containers from their ship.”
Subsea has employed Jason Coplin and Tony Keegan from Nelson Bay Fishing to charter the trips out to sea for the sonar and ROUV searches.