Earthquakes risk in Connecticut

Earthquakes in Connecticut: what you need to know

Connecticut is not on a major tectonic plate boundary like California, but it still experiences earthquakes. The state sits within the North American Plate, where old faults and fractures in the earth's crust can release built-up stress and cause ground shaking. The USGS Earthquake Hazards Program monitors these events, and small earthquakes are periodically recorded in Connecticut and across the Northeast.

On FEMA's National Risk Index, Connecticut's earthquake hazard is rated level 2 out of 5. That means the risk of damage is relatively low compared with other states, but it is not zero. The index uses historical data to estimate the expected annual loss from earthquakes. For Connecticut, that number is small, but the state has experienced earthquakes in the past and could feel a larger one in the future.

One quirk of earthquakes in the Northeast is how far they are felt. Since the bedrock under New England is older, denser, and more continuous than out West, seismic waves travel through it with less energy loss. As a result, a moderate earthquake in Connecticut could be felt over a much larger area than a similar earthquake in California. This does not necessarily mean more damage, but it can alarm more people.

Most of Connecticut's observed seismic activity has been concentrated in the eastern part of the state, according to USGS catalog data. However, seismic events can occur anywhere. The Connecticut Division of Emergency Management and Homeland Security (DEMHS) includes earthquakes in its all-hazards planning and encourages homeowners to understand that "low risk" does not mean "no risk."

How earthquakes affect homes

Even a small earthquake can shake a home enough to cause damage, especially if the structure is older or not securely anchored. Typical damage from ground shaking includes:

• Cracks in foundation walls, concrete slabs, or masonry.
• Drywall and plaster cracks, particularly around doorways and window frames.
• Chimney damage, which can be a fire hazard if bricks fall and block vents.
• Toppling of unsecured furniture, appliances, or water heaters.
• Broken windows from shifting frames.
• Gas leaks or water pipe breaks, which can cause secondary disasters.

In Connecticut, many homes were built before modern seismic building codes were introduced. The Federal Emergency Management Agency (FEMA) notes that older houses may lack adequate anchorage between the foundation and the frame, making them more vulnerable to shifting during an earthquake.

Regarding insurance, it is important for Connecticut homeowners to know that standard homeowners insurance policies do not cover earthquake damage. Earthquake coverage is sold separately, either as a rider on your homeowners policy or as a stand-alone policy. The premium reflects the state's low-to-moderate hazard level, so the cost may be modest compared with West Coast states. Contact your insurance provider to ask about earthquake coverage and what it would cost to repair or rebuild your home.

How to prepare your home

Even in a low-risk state, taking a few inexpensive steps can reduce damage and injury during an earthquake. The Ready.gov earthquake preparedness guide suggests these actions:

• Secure large furniture. Anchor bookcases, filing cabinets, and televisions to wall studs with brackets or straps.
• Use child-safety latches on upper cabinets to keep dishes and glassware from flying out.
• Strap your water heater. An unsecured water heater can tip over, break the gas line, and start a fire.
• Install flexible gas connectors on stoves and dryers to prevent leaks.
• Check and repair foundation cracks. Consult a structural engineer if you see serious cracks or settling.
• Retrofit unreinforced masonry chimneys or consider reinforcing them with metal straps to prevent collapse.
• Store heavy or breakable items on low shelves and secure any tall, narrow furniture to the wall.
• Create a household emergency plan and a disaster supply kit with at least three days of food, water, and medications.
• Practice "Drop, Cover, and Hold On" during an earthquake: drop to your hands and knees, take cover under a sturdy table, and hold on to the table leg until the shaking stops.

For homes with crawl spaces, consider bracing or creating a continuous load path from the roof to the foundation. FEMA offers detailed guidance on earthquake retrofitting, and the Ready.gov site has resources for renters and homeowners alike.

Frequently asked questions

Can a large earthquake hit Connecticut?

While the risk is low, it is not impossible. The USGS and FEMA's National Risk Index classify Connecticut as having a 2 out of 5 hazard level. The state has a history of small to moderate earthquakes, and larger earthquakes have occurred in the Northeast, such as the 2011 Mineral, Virginia earthquake that was felt across the region. Connecticut's bedrock can transmit shaking efficiently, so a remote earthquake could still produce noticeable shaking in the state.

Does homeowners insurance cover earthquake damage in Connecticut?

No, standard homeowners insurance policies exclude earthquake damage. To be covered, you must buy a separate earthquake insurance policy or add an earthquake endorsement. Even if the risk is low, earthquake coverage offers financial protection against ground-shaking damage, which can be expensive to repair. Talk to your insurance agent about the cost and benefits.

What should I do during an earthquake if I am at home?

If you are indoors, the recommended action is to drop to your hands and knees, cover your head and neck under a sturdy table or desk, and hold on until the shaking stops. Stay away from windows, bookcases, and heavy objects that could fall. If you are in bed, stay there and cover your head with a pillow. Do not run outside during the shaking, because falling debris is dangerous.

Official resources

• Connecticut Division of Emergency Management and Homeland Security
• USGS Earthquake Hazards Program
• Ready.gov – Earthquakes
• FEMA Earthquake Safety