120 Years Ago, Earthquake Shook S.C., Killing 100

It was the biggest natural disaster in South Carolina before Hurricane Hugo. On Sept. 8, the 120th anniversary of the Charleston earthquake passed quietly.

The magnitude 7.3 earthquake on Aug. 31, 1886, killed more than 100 people and destroyed about $5 million worth of property — worth $103 million when adjusted to 2005 figures for inflation. It was as powerful as the quake that rattled San Francisco and interrupted the World Series in 1989.

The earthquake remains the most widely felt historic earthquake east of the Mississippi River, said Ken Peters, a retired University of South Carolina history professor.

“It stands to date as the most damaging natural disaster to hit South Carolina prior to Hurricane Hugo back in September 1989,” Peters said.

Historical data suggests such a large quake should only come once every 500 years. But a magnitude 6 quake is expected with more frequency. Those quakes can cause severe damage, experts say.

The 1886 earthquake happened along a 25-mile fault near Summerville, said Pradeep Talwani, who is a professor of geophysics at the University of South Carolina and director of the South Carolina Seismic Network.

Back then, there was little development out there, with most of the damage happening in Charleston.

Structures like the new Cooper River bridge have been built to withstand events such as the 1886 quake but many other buildings haven’t, said Talwani, who has been monitoring earthquakes in South Carolina since 1974.

Modern engineering can protect structures against earthquakes, but the techniques add up to 10 percent to the cost of a building and aren’t used in the Lowcountry, Talwani said.

Recently, two quakes offshore of Charleston in 2002 reached magnitude 4. Those kind of quakes are expected every four or five years and can throw objects off shelves and put cracks in walls, Talwani said.