Potential environmental impact if this ship sinks?

Found this article on CNN:


The 654-foot Cougar Ace, which was carrying nearly 5,000 cars from Japan to Canada, had rolled practically onto its side.

My science-fu is weak. I’d assume the cars have no fuel, but still, there’d be a lot of batteries and automobile fluids in play eventually. Would salt water corrode the various car innards and release all that gunk into the ocean? How much damage would it do?

Probably little more damage than that caused by the Rubber Ducky Disaster of 1992.

The gas in the tanks of the cars (there will be a couple of gallons in each car) is peanuts to the oil in the bunkers of the ship itself.
The batterirs have H2SO4 in them, but again not in huge amounts. What maybe a pint pint and half in each battery?
For a idea of how this ships are built do a goole on 'Tricolor" a car carrier that sank in the English Channel back in late 02 IIRC. They sawed the ship into sections to raise it. On the pictures, you can see how the ship is built. These ships are great big parking garages. No water tight doors. Spring a leak and you are done.
Link to the Tricolor salvage website photo page (worth the click)

I can get you a deal on a slightly damp Volvo :smiley: :eek:

Well worth the click, although that cutting wire left some massive burrs along the hull sections. I hope they’ve also got a giant file to remove them!

Whether they would bother raising the vessel if she sinks would depend upon where she sinks. The Tricolor had to be raised because it was a danger to navigation in one of the busiest shipping lanes in the world. It was only just below the surface, and the wreck was hit twice after it sunk by other ships despite navigational warnings, bouys etc.

If this one sinks, and sinks deep, it may well never be recovered.

Rick is correct about the pollution risks. The cars are trivial. The will have a little fuel in their tanks (they drive in and out) but that’s nuthin’. Gas is too volatile to be a concern. Similarly brake fluid. The acid in the batteries would be a drop in the ocean (ahem).

I heard she has 600 tonnes of bunkers on board. That’s not very much in the scheme of things, but still enough to make a fair mess locally, if she leaks. However, whether they will depends on whether/where she sinks. If she goes down softly in deep water, the tanks probably won’t corrode open for a good few decades. And anyway, HFO (heavy fuel oil, aka bunkers) has a viscosity so high that it is semi solid unless heated, so in deep cold waters it will coagulate in the tanks.

This is a gross oversimplification. These ships have massive amounts of bouyancy and separation both horizontally (decks) and transversely (bulkheads). However, they do have a vulnerability to free surface effect.

I have been onboard a Wallenius car carrier. Think of a giant parking garage. The decks (when configured for cars) are about 5’8" from deck to the bottom of the beam for the next deck. Ramps between decks. Lust like the tightest parking garage you have ever been in. I saw no water tight doors anywhere below decks. (I admit I did not go to the lowest deck to check)
The Tricolor sank in 30 minutes. Doesn’t sound very compartmentalized to me.

I’ve been on car carriers many times.

You may not have realised it, but the ramps lift up and become watertight doors, and there are transverse divisions between several holds.

For examples of this sort of thing, see here and here andhere

For a good description of the whole Tricolor incident, see here (warning: massive .pdf). Check pages 38 and 74 for a description of the watertight divisions of the car decks, and how this was unfortunately negatived because various watertight hatches and doors were left open.

Put the two stories together and here’s an interesting question… if a shipload of (original) VW Beetles had sunk, how far would they have floated…? :stuck_out_tongue: