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.

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.

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.