When a dock, deck, or lift near the water in Charleston sags or tilts, the durable fix is to carry its weight past the soft pluff mud to firmer soil, usually with helical piers.
866-398-9323Licensed seawall specialists — FL · GA · SC
Seawall Repairs by Solid Foundations provides marine foundation repair in Charleston, SC for creek-front homeowners, HOAs, and marinas. Typical projects include helical piers under sagging dock walkways on Johns Island, re-leveling boat lifts on West Ashley creeks, and lifting settled patios behind Daniel Island bulkheads. Call 866-398-9323 or use the quote form to book a free on-site inspection.
Nearly all of these come from soft soil that can't carry the load or soil escaping through the wall.
Two reasons stand out. First is pluff mud, the thick Lowcountry marsh soil built from fine sediment, decaying cordgrass, and microbes in an oxygen-poor setting (S.C. Sea Grant). It's soft and spongy, and a footing resting on it keeps sinking.
Second is made land. Parts of the Charleston waterfront were built by filling in the water. The Low Battery itself sits on land reclaimed between 1909 and 1919, and its original concrete wall rested on a timber deck supported by timber pilings (City of Charleston). Filled ground tends to keep settling, and old timber support can decay.
The answer in both cases is the same: go past the weak layer to soil that can carry the load. Shimming a sagging dock or re-setting pavers on the same soft ground only buys a season or two. Transferring the weight down is what stops the cycle of settling and patching.
Steel shafts with screw-shaped plates are turned into the ground until torque readings show they've reached firm soil. We then bracket them to the structure and raise it toward level. They suit dock landings, lifts, decks, and small outbuildings. See helical pier installation.
Where soil has washed out from under a patio or pool deck, polyurethane injection fills the gaps and can lift the slab back toward level.
Rotted or borer-damaged pilings can be wrapped, sistered, or supplemented.
If soil is leaving through the bulkhead, we pair the foundation work with bulkhead repair in Charleston so the ground stops moving.
Typical Charleston pricing is $700–$2,000 per helical pier and $8–$25 per board foot for void fill. Most residential marine foundation repairs run $5,000–$25,000, depending on pier count, depth to firm soil, and access.
South Carolina's dock rules give owners some breathing room. Under SC Regulation 30-12, a destroyed dock may be rebuilt to its previous configuration as long as reconstruction is finished within five years of the event, unless there are extenuating circumstances (SC Reg. 30-12). Repairs that keep a dock in its existing footprint are generally simpler than expanding it. For a full rebuild or a new layout, see marine construction in Charleston, or start with our Charleston seawall repair overview.
We also handle marine foundation repair in Beaufort and Hilton Head.
That spot usually sits on the softest ground on the lot, where upland soil gives way to pluff mud. Helical piers carry that end down to firmer soil.
Often, yes. If the pilings are sound but have settled, we add support and re-level. Damaged pilings are replaced or supplemented.
As deep as needed to reach firm soil, which changes from lot to lot. Torque readings confirm each pier's capacity.
Not right away. SC rules generally allow a destroyed dock to be rebuilt to its prior layout within five years of the event.
Licensed, insured, NCFI-certified. Serving Florida, Georgia & South Carolina since 1996.
866-398-9323