South Carolina Dam Hazard Classification
South Carolina classifies dams by what happens downstream if they fail, not by how big they are. The criteria are in S.C. Code Regs. 72-1 through 72-9.
South Carolina's size exemption reads and where North Carolina's reads or — the same two numbers, 25 feet and 50 acre-feet, with the opposite effect.
The classes
| Class | Criteria |
|---|---|
| High | Failure will likely cause loss of life or serious damage. |
| Significant | Failure will not likely cause loss of life, but will cause damage. |
| Low | Failure may cause minimal property damage. |
Size classification
Size is a separate axis from hazard, and it drives design criteria rather than whether the dam is regulated.
| Size | Criteria |
|---|---|
| Very Small | Under 50 acre-feet and under 25 feet |
| Small | 50–999 acre-feet or 25–39 feet |
| Intermediate | 1,000–49,999 acre-feet or 40–99 feet |
| Large | 50,000+ acre-feet or 100+ feet |
Why classification decides everything else
Classification is not an administrative label. It determines whether an emergency action plan is required, what design flood the spillway must pass, and how often the dam is inspected. Getting it wrong in either direction is expensive: too low and the owner is out of compliance, too high and they are designing to a storm the structure never needed.
Worked end to end for a real structure: the flood rise test that separates the middle tier from high hazard, and the breach analysis behind it.
Scope. General information about South Carolina dam safety regulation, read from primary sources and current as of 2026-08-28. Not an engineering opinion about any specific structure and not legal advice. Requirements change when the legislature amends the Dams and Reservoirs Safety Act or the rules are revised — confirm against the current text of S.C. Code Ann. ยงยง 49-11-110 et seq. and S.C. Code Regs. 72-1 through 72-9, and contact the South Carolina Department of Environmental Services (SCDES) for a determination that binds.