Mapping Project Looks At Charleston Harbor As Battlefield
By Scott C. Boyd

(April 2009 Civil War News)

CHARLESTON, S.C. — The entrance to the harbor in Charleston – the scene of much naval activity during the Civil War – will be mapped to produce the nautical equivalent of a detailed map of a large battlefield on land.

The Maritime Research Division (MRD) of the South Carolina Institute of Archaeology and Anthropology (SCIAA) at the University of South Carolina is running the project, supported by a $28,348 grant from the National Park Service’s American Battlefield Protection Program.

The grant, one of 32 projects totaling $1,367,144, was funded last summer. Jim Spirek, an underwater archaeologist with the SCIAA, is the project leader. He knows the Charleston Harbor area because of his prior work on the submarine H.L. Hunley recovery team and some other work to identify wrecks in the harbor.

A number of Civil War-era ships sank in Charleston Harbor, both accidentally and deliberately. “We’re trying to precisely locate where the shipwrecks are and other features,” Spirek said.

Something that sets this project apart from others is how it views what happened in Charleston Harbor during the war.
“The main thrust is to look at this as a battlefield – as sort of a collective whole rather than individual sites, such as the Hunley-Housatonic [location],” he said. “We’re trying more of a total look at it.”

As a battlefield, the harbor saw fighting almost continuously for four years, something not claimed for any battlefield on land.

Following some preliminary archival research, Spirek’s team took their boat into Charleston Harbor on March 9 to begin the remote sensing phase of the project. Spirek said they would spend about three weeks on the water, with some time ashore reviewing the data collected. The boat work will be concluded in April.

They are using a cesium magnetometer, which detects slight changes in strength and direction of magnetic fields, to search for the presence of ferromagnetic material such as iron anchors and cannons.

They will also deploy a sub-bottom profiler, which uses narrow acoustic beams, as in sonar, to penetrate below the muddy bottom of the harbor and obtain further data on the presence of objects of interest.

Among the wrecks Spirek’s team will be searching for are three Union ironclads.

The Keokuk featured a turtleback deck with two non-rotating towers, each containing three gunports and one XI-inch Dahlgren smoothbore gun, as well as a novel armor arrangement.

It somewhat resembled a monitor but was not one. She sank on April 8, 1863, one day after Rear Admiral Samuel F. Du Pont’s naval attack with nine ironclads against the Confederate forts ringing the harbor entrance.

The Keokuk’s poorly conceived armor was penetrated 19 times by the enemy guns. Unable to retreat with the rest of the squadron after Du Pont realized the futility of his attack and withdrew, the Keokuk anchored two miles off Morris Island and by the morning had sunk in 15 feet of water.

The Confederates later pulled the two Dahlgrens from the Keokuk and used them to assist in the defense of the city. One of them can be seen today at Battery Park by the water’s edge in the city.

The Weehawken was in the Passaic class of monitors, the first ones built after the original Monitor. She was hit and damaged in Du Pont’s April 7, 1863, ironclad attack and then distinguished herself by almost single-handedly defeating and capturing the Confederate ironclad CSS Atlanta near Savannah, Ga., on June 17, 1863.

The Weehawken foundered off Charleston on Dec. 6, 1863, because an improperly distributed new load of ammunition disturbed the trim of the ship. The bow dipped, she took on water, and sank off Morris Island in 30 feet of water.

The Patapsco was another Passaic class ship. On Jan. 15, 1865, while assisting several small boats trying to clear the harbor channel between Forts Sumter and Moultrie of torpedoes (and other obstructions), she struck a torpedo and sank immediately in 33 feet of water.

The Union Navy sank “stone fleets” to block the entrance to Charleston Harbor in December 1861 and January 1862. These were old wooden sailing ships (New England whalers) that were filled with stone and scuttled. They were not very successful, but are among the wrecks Spirek said he will be looking for.

Three of the four commissioned ironclads of the Confederate Charleston Squadron were scuttled on Feb. 18, 1865, when The Confederates evacuated the city upon the approach of Gen. William Sherman’s army. (The other ran aground in January 1865 and was later seized by Union forces and sent north.)

These sites are too far from the harbor entrance to be in the scope of the project. Additionally, Spirek said these sites were where the main shipping terminal is, and probably were destroyed by dredging to keep the harbor hospitable to incoming commercial vessels.

Charleston was home to many successful blockade runners. Some not-so-successful vessels ended up beached on the sandy islands at the harbor entrance. Over time, the ocean receded from some, leaving them buried under the shifting sands.

After the work in the harbor by boat is concluded, the next phase of the mapping project will move to land and include searching for four of these buried blockade runners using ground-penetrating radar. Spirek said this should take place in May.

There will be viewshed analysis as well. Spirek said certain parts of the harbor visible from a fixed vantage point, and of historic significance, will be compared with their appearance during the Civil War to document any changes.

This will also serve as a baseline when assessing the impact of future development on the preservation of the historic viewsheds in the area.

Spirek said the mapping project will be finished after he has completed a detailed report on his findings. There will be extremely precise, GPS-labeled information on the location of the wrecks they find. 

To prevent this data from being used by scavengers, there will be two versions of the final report. One will be for use by governmental or other organizations involved with the Charleston Harbor area, such as the Army Corps of Engineers, the NPS and the SCIAA, and will have the full data.

A second version for public release will have less detailed information on exact shipwreck locations. The report will be printed and also posted on a project Web site.

The project will conclude by the end of the year.