Thursday, June 22, 2017

Out of the water: CSS Georgia casemate section is remarkably preserved

(Video by Panamerican Consultants Inc., via USACE)

One down, and one much bigger piece to go.

Crews working from barges in Savannah, Ga., on Wednesday evening lifted a 20-foot-by-24-foot piece of casemate that once protected the Confederate ironclad CSS Georgia.

Officials are excited because it includes a corner of the structure

Timbers used to support the armor – which was made from joined railroad iron – were “massive and so impressive,” said Jeremy S. Buddemeier, new media and social media manager for the U.S. Army Corps of Engineer’s Savannah office.

Stephen James, leader archaeologist with Panamerican Consultants, one of the contractors on site, told the Picket on Thursday afternoon that the wood "is shiny smooth, just like it was cut." The piece was lying in the mud, with the armor up and the wood down.

A bottom timber appears to be a foot in diameter, while the upper layer is about 6 inches in diameter, he said.

Corps senior archaeologist Julie-Morgan Ryan said that a mix of roots, biomass and mussels had covered and preserved the artifact with up to 3 feet of sediment, Buddemeier said. That layer protected the 47-ton casemate from wood-damaging Teredo worms that were evident in 2015 recovery dives.

The Corps is removing the scuttled vessel’s wreckage as part of a massive harbor deepening project.

They placed a prefabricated frame under this particular piece of armor, which is called the east casemate because of its position in the debris field.

Section of CSS Georgia casemaste (USACE)

Divers are having to deal with the Savannah River’s strong current and are working around “slack tides” that can have them in the water longer. They were able to do three dives Wednesday and the daylight and the tides lined up for the east casemate lift, officials said.

Next up is the west casemate, which is about 68 feet by 24 feet and weighs an estimated 120 tons. Lifting that one intact will be a bigger challenge, requiring beams and two cranes.

The earliest that lift will occur is next weekend, the Corps said. Following that comes the mechanized phase, in which a clamshell device will scoop up remaining artifacts from the river floor.

The U.S. Navy, which owns the shipwreck, would like to see artifacts and a reconstructed section of casemate to be displayed in a museum. James said in order to conserve the two casemate sections, conservators would have to separate the iron and wood.

And while the timbers that came up Wednesday are remarkably preserved, he said, they probably wouldn't hold up in the open air, even after extensive conservation. A display could feature the iron armor and new wood.

The crews will rebury the casemate sections in a secure part of the river until a decision is made on future conservation. For now, the east casemate, resting on a barge, is being kept wet with sprinklers.

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