CHARLESTON, S.C. (WCBD) – A plan to combat sea level rise, mitigate flooding and prevent storm surge in the City of Charleston includes the creation of a perimeter storm surge wall around the peninsula.
Details about the plan were released Monday by the U.S. Army Corps of Engineers Charleston District.
The report comes after months of studying, modeling and workshops. It included an overview of the study’s multi-tier analysis which outlined what the USACE called an ‘economically viable solution’ that would reduce the risk of damages from future coastal storm surge and sea level rise on the peninsula.
“It’s important to emphasize that this study is still in the preliminary stages,” said Lt. Col. Rachel Honderd, Charleston District commander. “Since day one, the study team has worked closely with the city to maximize the degree to which any incorporated measures complement the local historic setting and offer the community a cost-effective reduction of coastal storm risks.”
Conceptual layouts provided in the study aim to lower the impacts on the local ecosystem or the city’s historical character, while providing substantial flood risk reduction benefits to the Charleston peninsula.
The plan tentatively includes three features: a perimeter storm surge wall, an off-shore wave attenuator and nonstructural flood-proofing.
The Army Corps of Engineers says the perimeter wall is the current front runner.
USACE says the wall would be approximately 7.8 miles long around the perimeter of the peninsula. It would be primarily built on land, but the study says building in saltmarshes and wetlands may be unavoidable in some areas.
Permanent and temporary pump stations are proposed to efficiently move floodwaters and minimize the potential for water quality impacts.
The city is also looking into recreational features for the wall, including a walking path similar to the promenade on the current Battery wall. It would also be designed to be consistent with the city’s history and culture.
If approved, funded and implemented, the project would provide an estimated $175 million of annualized benefits to the city, according to The Army Corps of Engineers.
Designs, exact layouts and other specific plan details are not finalized. If Congress authorizes additional movement on the study, it would be refined during the optimization and design phases.
The Army Corps of Engineers encourages the public provide input on the draft report, which also includes an assessment of environmental impacts and a summary of their findings.
“At this point in the study’s progress, public feedback is critical,” said Honderd. “We’ve been tasked to investigate the peninsula’s vulnerability to coastal storm events, and we’re committed to creating a solution that best mitigates its coastal storm risks and damages while protecting the local environment.”
Officials have extended the public comment period from 30 to 60 days because of the coronavirus pandemic. The community is encouraged to provide feedback on the draft report electronically or by mail through June 19.
To learn more about the Charleston Peninsula Study and obtain the full draft report, visit www.sac.usace.army.mil/charlestonpeninsulastudy or check out the study visual outline at https://arcg.is/0HHiSf.