Explosives to break up barge carrier in Jacobs BayFebruary 19, 2010 by: admin
By Melanie Gosling
The wreck of the massive barge carrier Margaret, which towers over Jacobs Bay like a block of flats, will be broken up using explosives in a controlled demolition operation that will topple its cargo of smaller barges into the sea.
This is the sad end to what was a brand-new barge carrier when it ran aground on June 24 after the tug towing the vessel lost the tow connection in a storm near Saldanha Bay.
The barge carrier, which stands about eight storeys high, and its cargo of 12 river barges and two floating dry docks, were valued at around e30 million (about R300m). When it went aground, the vessel, which has no engines, was being towed from the shipyard in China where it was built to its owner in Rotterdam.
Debbie James of Samsa said on Thursday they were concerned that if they left the Margaret, it would become a safety hazard as the waves would weaken and break up the structure, and so had instructed the salvors Smit Amandla Marine to remove the wreck.
Taxpayers will foot the bill. Any of the barges or dry docks that are saved will be sold by Samsa to defer costs.
Kevin Tate, salvage master at Smit Amandla Marine, said they were not going to blow up the wreck, as had been done with the Jolly Rubino on the Zululand coast.
“This will be a sequential blast to undermine the structure so it will topple. We’ll use a total of 125kg of explosives at a time with a 42 millisecond delay in between, so you’ll get a ripple effect instead of one massive blast. One big blast would blow out windows but this won’t. There will be lots of water and spray and a bit of flame and smoke,” Tate said.
On Tuesday the salvage team cut away the wall of the top dry dock, which has to be removed to allow four of the river barges to slide into the sea after the blast. The 91 ton steel wall, which caused a 30m-high splash when it landed, has been towed to Saldanha Bay and sold.
“The top four barges are in good condition and can probably be saved,” Tate said.
Preparation work included plugging the dewatering holes in the barges and cutting the fastenings that secure them.
The explosion will take place at the end of the month.
Everyone within 500m of the wreck will be evacuated an hour before the explosion and the access road to Jacobs Bay will be closed three hours before the blast.