The submerged bottomlands of North Carolina are any land underwater in the state. This includes mountain rivers, Piedmont lakes, coastal sounds, and 3 miles out to sea. In these bottomlands, archaeologists encounter a huge variety of sites beyond shipwrecks. Villages, homesteads, cemeteries, abandoned vessels, and battlefields all exist under our waters. Any resource that becomes submerged falls into the realm of underwater archaeology. The Office of State Archaeology's Underwater Archaeology Branch manages and protects these resources.
While all submerged sites are subject to climate change effects, threats vary by geography. For example, the wreck of Argonauta on the coast will experience water acidification and sea level rise. The wreck of the Yadkin River Hurt Ferry in the mountains is more susceptible to the effects of extreme weather and flooding.
The impacts of these threats can be similar. Changes in sea level, precipitation, and extreme weather events all result in erosion. Along waterways and shorelines, this moves sediments and exposes or covers sites. Changing site environment has a huge effect on site preservation. For example, remote sensing of the blockade runner Ella showed storms between 2012 and 2016 removed sediment. This left more of the wreck exposed to water and sea life damage.
Archaeological sites along the Atlantic coastline face an array of threats that alter their chemical and physical environment. Sites that are partially submerged, like those along Eagle Island in Wilmington, will become submerged by sea level rise. Submersion alters the effect of waves on the sites and can sometimes help sediment bury them. While this can be beneficial, the associated changes to ocean chemistry are not. Acidification encourages corrosion of metal, which could cause sites to collapse. Warming temperatures and changing salinity invite new organisms to the changing ecosystem. This can be particularly dangerous for wooden site elements as wood-eating sea life arrives.
This material was produced with assistance from the Emergency Supplemental Historic Preservation Fund, administered by the National Park Service, Department of the Interior. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the Department of the Interior.