What next for the stricken Costa Concordia?

As hopes fade of finding more survivors of the Costa Concordia disaster, the next question is whether the ship itself can be rescued.

Taller than six London buses, weighing 114,500 tonnes, and currently seemingly wedged on its side on the Italian seabed, it is a big question.

Mike Lacey, secretary general of the International Salvage Union, told Channel 4 News it is also an expensive one.

“It will be expensive – tens of millions, up to £100m,” he said. “But nothing is impossible. If you throw enough money at it you can do anything.

“When they found the Titanic someone asked me if it could be raised. If you can fly a man to the moon hundreds of thousands of miles away, then you can lift a ship that’s thousands of feet below. But it’s a question of economics.”

Get the fuel out

Mr Lacey said the first priority is getting the fuel out, which Smit, a Dutch salvage company, is currently working to do.

“There are 2,000 tonnes of fuel on the vessel and clearly if that starts leaking out, that’s an environmental disaster,” he said. The Italian government is also worried about this – and is set to declare a state of emergency and pledge funds to try to prevent it from happening.

If you throw enough money at it, you can do anything. Mike Lacey, International Salvage Union

Mr Lacey said a number of other operations will be ongoing at the wreck at the same time as extracting the fuel, which could take weeks.

“There will be lots of survey work being done to ascertain, to the extent they can, the extent of the damage. You can see the damage on the bottom of the port side of the ship. There’s possibly damage on the starboard side on the bottom – there will definitely be damage on the starboard side of the hull where she is in contact with the seabed,” he said.

All of these issues will be taken into account when the operator of the Costa Concordia, Costa Cruises, decides what can be done with the ship.

“Not least will be the decision by the owner and the insurers as to whether they consider the ship is repairable. Can it be salvaged? They will also work with salvage companies to look at how they can do it, how long will it take, what will it involve.

“The alternative decision may be that this ship is beyond any conventional salvage attempt and she is going to have to be cut up. This has happened before and no doubt it will happen again,” Mr Lacey told Channel 4 News.

Salvaging the ship

If the operators and insurers decide they want to try and salvage the ship, first they have to get her upright – to get her afloat, so she can sail away for more comprehensive repairs. This is more complicated than it sounds.

A number of methods, involving air bags, cranes, winches and barges will be used to attempt to get the Costa Concordia back upright. Teams would also have to try and seal damage done to the ship and pump out the water, otherwise any water that they pump out will just pour back in and re-sink her.

“The worst bit in trying to get her upright is the first bit,” said Mr Lacey. “Once you get her up it gets easier all the time.”

The company has referred to a method of using air balloons to push the ship towards an upright position. This involves getting extremely strong inflatable air bags which could be positioned on the coastal side underneath the ship.

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“Then you inflate them, and they either go bang or they push the ship up,” explains Mr Lacey.

“But they will never push the ship all the way upright. All they can do is contribute – if the ship is 80 degrees over, they could bring her to 60 degrees.”

At that point, the winches and barges get involved. There are precedents for this operation, such as the operation used on the Herald of Free Enterprise, a car ferry which sank in 1987 with 193 lives lost.

Barges with huge winches could slowly heave the ship back upright – these would have to be secured to the seabed, otherwise all that would happen is the barges would move towards the ship.

“It’s about the turning point,” said Mr Lacey. “If you could come up with a steel rod 1,000 miles high and put someone on the end of it, he could turn the ship the right way up no trouble at all. But it’s getting that turning point.”

Sliding risk

All of these operations also have to take into account the risk of the ship sliding off the bank and into deeper waters. This is a potential risk – although apparent movements seen so far could just be the ship shifting slightly as it gets pierced again by rocks, Mr Lacey said.

If it seems this may happen, one of the only ways to prevent the full sinking would involve building a massive structure on the shore to effectively anchor the ship in place.

However, slipping below the water is the “worst case scenario”, Mr Lacey said. If it happened, floating cranes and cutting equipment “that can go through steel like a knife through hot butter” would have to be brought into the operation.

But if this worst case scenario is avoided and the ship is righted, she could still be scrapped.

“The final decision will have to come from the owner and insurers, and advice from the salvage company as to what is possible. Also then there’s the economic proposition – is this ship repairable? And if the decision is no, even if they get it up, they may just say let’s go ahead and cut it up,” Mr Lacey said.