This is one of 19 Revolutionary War-era cannons brought up from the bottom of the Savannah River as part of the Savannah Harbor Deepening Project. (Photo courtesy of Savannah Engineer District)
Dredging & Marine Construction

Dredging Project Unearths 19 Cannons In Savannah River

About 13 months ago, a Weeks Marine dredge crew turned up three cannons, an anchor and a timber during dredging operations in the vicinity of Old Fort Jackson on the Savannah River, a couple of miles east of the city of Savannah, Ga.

A discovery of that nature was not unexpected in Savannah, an area that has played a large maritime role in the history of the United States, dating back to the city’s founding in 1733.

But few could have predicted all that the U.S. Army Corps of Engineers’ archaeology team—including Commercial Dive & Marine Services Inc. and Commonwealth Heritage Group—would discover in the year that followed.

In all, a total of 19 cannons have been recovered between February 2021 and February 2022.

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“The original three cannons were brought up by a clamshell dredge,” said Andrea Farmer, an archaeologist for the Corps. “The following 12 were brought up via lift bags by Commercial Dive & Marine Services Inc., with supervision by Commonwealth Heritage Group, the company that performed all sonar investigations. The final four were recovered through clamshell dredging.”

Besides the original three cannons and the recently recovered four 60-inch “short guns,” which were discovered between February 17 and 18 during dredging operations, the remaining cannons were recovered in November and December 2021 and placed in temporary storage in the river. They were then placed in wet vats beginning on January 18.

“All artifacts are in temporary storage at a secured location,” Farmer said. “The materials are being kept in wet vats until decisions can be made about future conservation. The conservation process involves electrolysis to desalinate the artifacts and remove any concretion. A finish will be applied, but the type is dependent on how the artifact will be stored and/or exhibited.”

Farmer said all 19 cannons were recovered from within the “Cannon Scatter Site” near Fort Jackson. The area where they were discovered offers some important clues as to their origin. 

“Historical records suggest that the cannons are from the HMS Savannah, especially maps indicating where this vessel sank,” Farmer said. “They also suggest that they could also be associated with the HMS Venus and/or other unnamed armed troop transports. Dr. Jim Jobling, former lab manager at the Conservation Research Lab at Texas A&M University, and Dr. Gordon Watts, executive director of the Institute for International Maritime Research Inc. and Tidewater Atlantic Research Inc., were brought in a consultants on this project.”

Farmer said the team is working to obtain a copy of the ship’s log or some other documentation from 1779 that would confirm the cannons came from the HMS Savannah or another Royal Navy ship. The HMS Savannah and other British ships were scuttled in the Savannah River in 1779 to block a fleet of French warships from approaching the city in support of the Americans.

“Future conservation will be performed to identify any distinguishing marks that may tie these artifacts to a specific vessel,” she said. “More archival research will be performed at that time, as well. Conservation will likely begin in the next year or two and is anticipated to take around two to three years to complete.”

The Corps is working in consultation with the Georgia Department of Natural Resources, the British Embassy and the Georgia and South Carolina State Historic Preservation offices on conservation, curation and exhibition possibilities. 

Dredging was suspended in the immediate vicinity for about a year to allow for thorough surveying and recovery efforts. Yet even with that, the resumption of clamshell dredging quickly turned up the final four cannons. The discovery and recovery of the cannons over the past year demonstrate how Savannah’s harbor now, as in the 1700s and 1800s, is a working river where commerce and history exist alongside one another.

“Development and growth are necessary in a city like Savannah, where increased river commerce is dependent on the ability to expand the harbor,” Farmer said. “When possible, archaeological sites are preserved as is. When that is not necessary, we must weigh the challenges and benefits to determine the best possible outcome. In this situation, the site was in the direct path of the deepening activities, so it was important to document the site and recover as many artifacts as possible in order to share more about the history of the site and Savannah at the time.”

The discoveries were made in the final stages of the Savannah Harbor Expansion Project, which increased the available draft in the Savannah River from 42 feet to 47 feet, which increases to 54 feet at high tide.

“Projects like the Corps’ Savannah River Harbor Expansion Project bring much-needed resources and attention to the submerged archaeological resources that would otherwise remain hidden,” Farmer said.

The Revolutionary War-era cannons weren’t the only significant naval artifacts discovered during the Savannah River deepening work. The Savannah District also salvaged the remains of the CSS Georgia, a Confederate ironclad gunboat, from the area near Fort Jackson during the project. Much of the ship was recovered between 2015 and 2017. Archaeological data recovery was completed late last year.

Through multiple stages of discovery and salvage efforts, archaeologists recovered more than 30,000 artifacts connected to the CSS Georgia, including 241 pieces of ordnance, five cannons and two large casemate sections of the ship.

“The\initial phase focused on the systematic identification, mapping and recovery of all small artifacts, vessel hardware and fastenings and the construction of an on-site web to facilitate subsequent relocation and recovery of large artifacts and vessel components, including ordnance, machinery and casemate structure,” said Brian Choate, the Savannah District’s physical scientist. “The second phase focused on the recovery of railroad armor, steam machinery and other heavy objects to finish clearing the site for the final phase. The final phase of on-site activity prepared and recovered segments of all three sections of casemate.”

Built in 1862, the CSS Georgia was an integral part of Confederate defenses of Savannah. In December 1864, during the final days of the Civil War and as Union Army Gen. W.T. Sherman was completing his “March to the Sea,” Confederate troops scuttled the CSS Georgia in the Savannah River.

“The completion of the CSS Georgia data recovery could not have happened without the combined efforts of USACE, the U.S. Navy, the U.S. Marine Corps, the U.S. Coast Guard and various state, federal and local agencies,” Farmer said last year after the ironclad recovery was complete. “Together, we have accomplished one of the largest archaeological excavations of a maritime site that has ever taken place in the state of Georgia and preserved an important part of our local history.”