Archaeologists from the University of South Carolina have wrapped up a five-year survey of the Charleston Harbor as they try to map out the 55 Civil War shipwrecks that cover its floor. It’s the first time that historians have ever mapped out the complete naval battlefield for the siege, which lasted from 1861 to 1865.
Underwater archaeologist James Spirek of the South Carolina Institute and Archaeology and Anthropology (SCIAA) helped lead the project on behalf of the National Park Service. “If we don’t know where the (artifacts) are, we can’t help protect them,” he told South Carolina Radio Network.
Most South Carolinians know that the Civil War began in the harbor with the Confederate shelling of a U.S. garrison at Fort Sumter in 1861. Later that year, the Union Navy began blockading the harbor in an effort to prevent supplies from reaching the South. There were also two naval attacks on the city before the war ended four years later.
Spirek used official records of the armed forces, along with 19th-Century charts, to help map out the modern locations of the wrecks. The team then used remote sensory equipment that could detect iron to find the exact coordinates. They then used side-scan sonar to image the ocean floor and detect any objects that could be sticking out from it.
Roughly half of the wrecks (29) are old whaling vessels that the Union Navy sank to block the entrance of the harbor. Known as the “Stone Fleets,” some of these vessels’ exact locations had been a mystery for decades until the SCIAA survey. “Most people thought they were buried under the sandbars, but apparently, they’re still exposed on the bottom of the harbor floor,” Spirek said.
Spirek said 16 of the wrecks his team identified were “blockade runners”— Confederate merchants who tried to avoid the Union ships and supply the city. Four federal warships and six Confederate vessels also lie beneath the waters.
The National Park Service approved a $28,000 grant for the project in 2008, which was matched by an additional $28,000 from the University of South Carolina.
Spirek was also able to locate several of the Union ironclad ships, known as “monitors,” by using previous survey reports and sonar technology and magnetometers.
These included the Patapsco, sunk by a mine near Fort Sumter; the Weehawken, which flooded in a storm; and the Keokuk, an experimental ironclad that sank after a severe pounding by Confederate artillery. Specific GPS coordinates were assigned to each wreck for future investigation.
The USC survey took nearly as long as the battle did more than a century ago, but the results are worth it, Spirek said.