Here's the recipe for the new bombproofs and traverses going up at North Carolina's Fort Fisher: Do research. Add precast concrete. Cover with a whole lot of dirt

Bombproof construction begins, pieces for tunnel entrance next to original traverses (Fort Fisher)

A construction project this summer at Fort Fisher State Historic Site in North Carolina is something you don’t see every day – or will likely see anywhere else.

Sections of precast concrete were placed Friday near a giant mound of dirt as crews begin to build a replica bombproof -- an earth- and timber-covered structure that protected a garrison from shelling.

The Civil War site near Kure Beach and contractors are engaged in an extraordinary effort to recreate three traverses, bombproofs, a magazine and a sally port that were vital parts of the Confederate fort, which fell in furious hand-to-hand combat in January 1865.

“This is a one-of-a-kind project,” said Ben Warren project manager with Bordeaux Construction of Morrisville, N.C. “We build much larger projects, but many things on this project are unique.”

Rendering of traverses, sally port and visitor center behind (Fort Fisher)

A portion of the vital fort’s earthworks was leveled during World War II to make way for an airstrip when the area was used to train anti-aircraft and coastal artillery units. The work is in conjunction with a new visitor center, also being built by Bordeaux Construction.

The earthworks project requires nearly three dozen pieces of precast concrete. About half have arrived, said Warren. The pieces were made by the Alcrete plant in Jacksonville, N.C.

Chad Jefferds, assistant site manager at Fort Fisher, told the Picket there will be a new tunnel allowing visitors to pass through the fort at the center sally port, as would have been the case originally, along with bombproofs under the traverses.

The traverses are being built in the same line as those that have withstood the effects of time and change. Rebuilding the fort will involve the reconstruction of the 7^th, 8^th, and 9^th traverses.

Click to enlarge to see rebuilt features, including tunnel and bombproof (Fort Fisher)

“You will not see the precast concrete tunnels, as they will be clad in wood, such that the tunnels will appear as though they were built from timber, same as they were built originally,” Warren said in an email.

Jefferds said the concrete will be placed, waterproofed and buried over the next several weeks “so that work can begin on the gun emplacements atop the recreated mounds. The current timeline for the work has everything being completed by early September, but this is all highly dependent on weather.”

The site, with the exception of a tour stop, closed in April. The new 20,000 square-foot visitor center, a significant upgrade, is just north of the east-west line mounds of earth known as traverses that were part of the defenses. Much of the eastern part of the fort has been claimed by the ocean. 

Visitors will use tunnel to explore  features in new traverses (Fort Fisher)

Crews will work to ensure any exposed portions of the concrete will be made to look like they appeared during the battle.

“Visitors will be able to walk through the tunnel and bombproofs, as well as up into the gun emplacements themselves,” said Jefferds.

“We are in the process of sourcing reproduction munitions, boxes, barrels, etc. to make the bombproofs appear as they may have during the Civil War.”

With the three traverses will come two gun emplacements, which will have a heavy cannon in each, along with two 12-pounder Napoleons in the center sally port.

The project will allow people to interact with the fort in a whole new way, as the tunnels and bombproofs have been caved in and inaccessible since the late 19th century, said Jefferds.

The new visitor center rises to the north of construction area (Fort Fisher)

The design of the recreated earthworks is based on historic maps, photographs and descriptions. Architectural and engineering firm Clark Nexsen made the designs, which will be similar to the original mounds, said Warren.

Dennis Stallings, design director for Clark Nexsen, said it had an archaeological consultant on its team, Commonwealth Heritage Group, which “provided documentary research along with archeological research and provided a comprehensive report on the original fort and its construction."

There were archeological investigations in 1970 and another in 1981 that provided context.

“We aimed to create earthworks that appeared historically accurate while seamlessly incorporating modern construction techniques,” Stallings wrote in an email. “This endeavor presented a unique challenge, as we found little precedent to guide us.”

“The reward is a project that is immensely satisfying as architects. It is a one-of-a-kind endeavor that millions of people will interact with over the coming decades,” he said.

New visitor center is in the middle, at left is current one, new traverses far left (Bordeaux Construction)

Fort Fisher was built on the peninsula between the Cape Fear River and the Atlantic Ocean, south of Wilmington.

On Jan. 15, 1865, after a naval bombardment, the Federal army attacked from the western, river side while Marines pushed in from the northeast bastion. The fall of the “Gibraltar of the South” cut off blockade runners and the last supply line through Wilmington to Robert E. Lee’s Army of Northern Virginia. U.S. Colored Troops were among those taking part in the attack.

Essentially everything between Shepherd’s Battery on the western end of the fort’s land face and the center sally port were the scenes of intense fighting during the US Army’s assault. The fighting went from along the traverses from west to east and was often hand-to-hand.

Jefferds said planning is underway for a grand opening ceremony, which should take place toward the end of September “if everything stays on schedule.”

Montage of Timothy O'Sullivan wartime photos of traverses; click to enlarge

The new museum will be three times larger than the current one, with more room for groups, educational space, rental opportunities, staff offices, etc. The exhibit area is also larger and will be based on the experiences of the place by the people who lived, fought, and died here.

While Fort Fisher is still the focus, the approach in developing our exhibits was much more driven by people, including underrepresented groups, said Jefferds.

“The (visitor center) exhibit casework and artifact installation will begin next week and will wrap up on the last week of August, at which time the only remaining work will be on the earthworks and fortifications,” said Warren.

The old visitor center has been torn down.

"Doing so allows us to create a better viewshed of the fort from the new visitor center as well as create green space for programming," said Jefferds.