The operation to lift the submerged 25-ton crawler crane out of the sea in New Zealand has proven successful. Titan Cranes Limited used a Liebherr LTM 1350-6.1 All Terrain crane to fish out the submerged crane.
The procedure finished early on Saturday afternoon, after the crane fell from Seaview Wharf, in Hutt Valley, into 12 meters of water on October 2.
CentrePort ferries and bulk general manager Andrew Steele said the crane’s cab was lifted from the water after 2 pm on the main wharf at Aotea Quay.
“I think it’s pretty safe to say that the crane won’t be usable again.”
The investigation into how the crane ended up in the water is ongoing and Worksafe has been advised. Fender replacement work on the Seaview wharf undertaken by GK Shaw Ltd has been suspended.
At 2.30pm on Saturday the crane was still hanging “vertically up” in the air with contractors working to get it back on the ground.
“The tracks are perpendicular to the cab, so they need to be brought together, otherwise the load would be too big to go on the road. Once we turn the cab around to be parallel with the tracks it’ll be put on a flat-bed truck and returned to its owners.
“It’s a real credit to the team who have been working on this. The operation has been reasonably well planned and executed very safely.”
Greater Wellington harbour master Grant Nalder said the moving of the crane was undertaken by New Zealand Dive and Salvage. It had been lifted with airbags and was towed from Seaview towards the Wellington city.
“[It was] getting towed quite slowly… It’s not the easiest thing to drag along.”
Nalder said no other sea traffic was at risk during the crane’s journey back towards the wharf.
“Due to the weather conditions, there’s not a lot of boats out there… and the crane is submerged, so it’s not at risk of hitting anything.
“We’ve provided advice to some of the clubs around the harbour that it’s moving, but given that they’re shifting it in bad weather, there’s not a great deal of boats out there”.
Nalder described the falling of the crane into the harbour as “unusual, but not completely unusual”.
“Objects have to get moved and lifted and they often end up in the harbour when they shouldn’t.”
The recovery operation to salvage the crane began on October 7. Divers cut up the boom into sections underwater. These were lifted out piece by piece on to the Seaview Wharf and removed. The work took two days.
The remaining cab was then moved clear of the wharf on October 11, where airbags were attached, lifting it slightly so it could be towed away. The cab was towed behind Soames Island before it arrived at Aotea Wharf.