Low Battery Seawall Restoration Project
Charleston, SC
Merit Award
Sent by: JMT
Owner: City of Charleston
Main design company: JMT
General contractor: Construction of the Gulf Stream
Geotechnical engineer: Schnabel Engineering
Instead of demolishing and replacing Charleston’s century-old low-battery seawall, the team developed an approach that maintained the base of the wall whenever possible and transferred the loads to a new micropile support. Crews restored the wall in 100-foot segments. Driving conventional piles would have required large cranes, expanded the footprint and risked damaging nearby historic homes. Instead, the micropiles preserved part of the old wall, generated less noise and vibration, and eliminated the need for an expensive shed.
Originally built between 1909 and 1919, the wall had deteriorated from age, storms and material degradation. This $64 million project reinforced the seawall with fiberglass reinforced polymer and the new foundation, which was designed to accommodate additional height against future storm events and sea level rise. In the salt water of Charleston Harbor, the team used GFRP reinforcement for the most susceptible areas of the wall. The project also raised and widened the boardwalk, improved pedestrian walkways, added ADA-compliant access points, traffic calming measures, and rebuilt drainage and water quality systems to modern standards.
