Construction of a backup dam immediately next to the Saluda Dam was completed in 2005 by the SCANA corporation . The construction was first proposed in 1989 but did not begin until 2002 . The roller-compacted concrete backup dam was required by the federal government as a mechanism for preventing flooding if an earthquake of similar magnitude to the 1886 Charleston earthquake was to occur again in South Carolina . It was projected that large parts of the Columbia , SC metropolitan region ( encompassing around 135,000 people ) would have been in the flood region if the original dam was damaged
1886 Charleston earthquake
1886 Charleston earthquake
Saluda Dam