Joint project begins process to restore Savannah saltmarsh habitat

USACE, Savannah District
Published March 11, 2022
SAVANNAH, GA. - Members of the U.S. Army Corps of Engineers, Savannah District visit the dredged material containment area 1S on the Savannah River, Georgia on Feb. 23. The Corps is in the early process of restoring 29 acres of saltmarsh at DMCA 1S as part of the mitigation requirements for the Savannah Harbor Expansion Project.

SAVANNAH, GA. - Members of the U.S. Army Corps of Engineers, Savannah District visit the dredged material containment area 1S on the Savannah River, Georgia on Feb. 23. The Corps is in the early process of restoring 29 acres of saltmarsh at DMCA 1S as part of the mitigation requirements for the Savannah Harbor Expansion Project.

SAVANNAH, Ga. – Members of the U.S. Army Corps of Engineers, Savannah and Jacksonville Districts began collaborating in February on a restoration project at the Dredged Material Containment Area 1S, located on the Savannah River near Port Wentworth, Georgia, as part of the mitigation requirements associated with the Savannah Harbor Expansion Project.

“Overall I think what is special about this project is we are restoring approximately 29 acres of dredged material containment area back to its original saltmarsh habitat,” said Alexander Gregory, a biologist working for the planning branch in the USACE, Savannah District. “The significance of this is saltmarshes provide essential ecosystem services such as carbon sequestration, protection from storm surges and floods, and nursery and foraging habitats for fisheries species.”

Gregory said their primary goals for the project are to naturally revegetate the site with the native species Spartina alterniflora, commonly known as smooth cordgrass; ensure adequate exchange of brackish surface water with pore waters located at the interior of the island; and restore natural tidal marsh features and hydrology throughout the next seven years. The process of revegetating is intended to reoccur naturally and passively but USACE is prepared to manage adaptively should the plants not colonize as predicted.

Because the Savannah District doesn’t have an unmanned aerial vehicle program, Thomas Spencer and Travis Bennett, from the Jacksonville District, traveled to DMCA 1S to scope out the site to determine where their UAV needs to go to document the long-term growth of the area.

“The Jacksonville District has a robust UAV program and they will be visiting us annually over the course of our post-construction monitoring to capture the change in conditions,” said Gregory. “They deemed it feasible and will come back this September to set baseline conditions.”

Gregory said they’re also partnering with the Vegetation Monitoring Group in the Jacksonville District which specializes in invasive species in case any problems arise during the restoration of the saltmarsh habitat.

DMCA 1S is located adjacent to the confluence of Savannah River’s Front River and Middle River within the boundaries of the Savannah National Wildlife Refuge. Much of the site is currently high ground because of the previous dredged material placement activities which were completed at least 20 years ago. Currently the site consists of mature and mixed forest, wetlands, and saltmarsh.