Earthquakes risk in South Carolina

Earthquake risk in South Carolina: what you need to know

South Carolina is not commonly associated with earthquakes, but it has a long history of seismic activity. The state is rated a level 3 of 5 for earthquake hazard, meaning there is a moderate chance of damaging shaking in some regions. Unlike the West Coast, where earthquakes happen along active fault lines at plate boundaries, South Carolina lies within the interior of the North American plate. This means earthquakes here are intraplate events, and they can occur without much warning.

According to the USGS Earthquake Hazards Program, the highest hazard in South Carolina is centered around the Charleston area, including the Lowcountry and parts of the coastal plain. The most famous and damaging earthquake in the state's history was the 1886 Charleston earthquake, which caused widespread destruction and was felt across the eastern United States. Since then, smaller earthquakes have occurred periodically, often in swarms, with a few felt by residents.

Unlike weather-related hazards, earthquakes do not have seasons. They can happen at any time of the day or night, and they are not influenced by climate. The risk is greatest in the southern and eastern portions of the state, but no part of South Carolina is entirely immune. The South Carolina Emergency Management Division monitors seismic activity and works with local agencies to promote preparedness across the state.

How it affects homes

Even a moderate earthquake can cause noticeable damage to homes, especially older structures that were not built or retrofit to withstand shaking. The most common types of damage include:

• Cracks in foundations and concrete slabs, which can compromise structural integrity.
• Chimney damage – masonry chimneys are especially vulnerable to toppling or cracking.
• Shifting or settling of a house on its foundation, particularly for homes on raised or crawlspace foundations.
• Broken windows, cracked drywall, and damage to unsecured furniture or appliances.
• Water and gas line breaks, which can lead to flooding or fire hazards.

In South Carolina, many homes are built on sandy or loose coastal soils, which can amplify shaking. Older homes in historic districts, such as those in downtown Charleston, may be particularly at risk because they were built before modern seismic codes. Even newer homes can be damaged if they lack proper anchoring or bracing.

Insurance is an important consideration. Standard homeowners insurance policies in South Carolina do not cover earthquake damage. Homeowners need a separate earthquake insurance policy or an endorsement to their existing policy. The South Carolina Department of Insurance provides guidance, and the FEMA Earthquake Safety page explains the basics of earthquake insurance deductibles and coverage. It is worth reviewing your policy and talking to your insurance agent about your options, especially if you live in the higher-risk Charleston area.

How to prepare your home

Taking a few practical steps can greatly reduce the risk of earthquake damage and injury. Here is a list of concrete mitigation measures recommended by emergency management experts:

• Secure heavy furniture – anchor bookshelves, cabinets, and televisions to wall studs using flexible straps or brackets.
• Install latches on cabinets – use earthquake-proof latches to keep cabinet doors shut and prevent items from falling.
• Brace your water heater – strap it to the wall to prevent it from toppling or rupturing gas or water lines.
• Anchor appliances – secure refrigerators, stoves, and other large appliances with anti-tip brackets.
• Hang heavy items away from beds and seating areas – mirrors, picture frames, and shelf displays can fall during shaking.
• Check your foundation – if you have a crawlspace, consider bolting the house to the foundation and adding shear bracing to cripple walls. Consult a licensed contractor or structural engineer.
• Replace brittle piping – use flexible connectors for gas appliances and water lines to reduce the risk of leaks.
• Store breakables safely – put glass items in low, secure cabinets or use museum putty to hold them in place.
• Keep an emergency kit – include water, food, flashlights, batteries, a first aid kit, and any necessary medications.

For more detailed retrofitting guidance, the Ready.gov – Earthquakes page provides step-by-step instructions on securing furniture and safely shutting off utilities.

Frequently asked questions

Can earthquakes really happen in South Carolina?

Yes. South Carolina has recorded earthquakes for over two centuries, and the state is considered a moderate-risk region. The 1886 Charleston earthquake was one of the largest earthquakes in the eastern United States, and smaller earthquakes are still detected by USGS monitors in the state today.

What should I do if I feel an earthquake in my home?

If you feel shaking, the recommended action is to Drop, Cover, and Hold On. Drop to your hands and knees, take cover under a sturdy table or desk, and hold on until the shaking stops. Stay indoors until the shaking ends, then check for hazards like gas leaks, broken glass, or structural damage.

Does homeowners insurance cover earthquake damage in South Carolina?

No, standard homeowners insurance policies do not cover earthquake damage. You must purchase a separate earthquake insurance policy or add an earthquake endorsement to your existing policy. These policies typically have high deductibles (5% to 15% of the home's value) and may have limits on certain types of damage, so review the terms carefully.

Official resources

• South Carolina Emergency Management Division
• USGS Earthquake Hazards Program
• Ready.gov – Earthquakes
• FEMA Earthquake Safety