Earthquakes risk in Wisconsin

Earthquake Characteristics in Wisconsin

Wisconsin is one of the least seismically active states in the nation. The USGS Earthquake Hazards Program classifies the state as having a very low earthquake hazard, and Wisconsin Emergency Management (WEM) rates the risk as Level 1 out of 5. This means that while earthquakes are not impossible, they are rare and typically minor. The state's stable geological setting makes it far less likely to experience damaging earthquakes than places like California, Alaska, or even the New Madrid Seismic Zone in the central United States.

Wisconsin lies far from the major tectonic plate boundaries that cause most of the world's large earthquakes. The state sits on stable continental crust, and there are no known active faults capable of producing strong, damaging earthquakes. According to the USGS, the few earthquakes that have been recorded in Wisconsin are generally small and typically cause no damage. For example, a swarm of small earthquakes near Clintonville in 2012 was widely felt but caused no significant damage. These events are often shallow, which can make them feel more intense near the epicenter, but they are still too weak to cause structural damage to well-built homes.

Because earthquakes are not tied to weather patterns, there is no 'season' for them in Wisconsin. They can occur at any time of year. The areas of the state that might be slightly more likely to feel shaking are those closest to known seismic zones outside the state, such as the New Madrid Seismic Zone in the central U.S. and the Wabash Valley Seismic Zone in Illinois and Indiana. However, even a very large earthquake in those distant zones would likely produce only minor, non-damaging shaking in Wisconsin. The entire state—from Milwaukee to Madison to Green Bay—shares this very low risk profile. In fact, the USGS National Seismic Hazard Map shows that the probability of a damaging earthquake (magnitude 6 or greater) affecting Wisconsin in any given year is extremely low, well below the threshold for typical engineering concerns.

How it affects homes

Given the very low earthquake risk in Wisconsin, the chance of a home sustaining earthquake damage is extremely small. In the rare event of a felt earthquake, damage would most likely be limited to cosmetic issues: cracked plaster or drywall, objects falling from shelves, and possibly small cracks in masonry or foundations. Homes with unreinforced brick or stone foundations—common in older neighborhoods—could be slightly more vulnerable to even minor shaking, but catastrophic structural failure is not a realistic concern in Wisconsin. Modern homes built to current building codes are generally very resistant to the level of shaking that might occur here.

From an insurance perspective, standard homeowners policies in Wisconsin typically do not cover earthquake damage. If you want coverage, you would need to purchase a separate earthquake insurance policy or add an endorsement to your existing policy. However, because the risk is so low, many insurers may not offer earthquake coverage in Wisconsin, or the cost may not be justified for most homeowners. It is always a good idea to check with your insurance agent to understand exactly what your policy covers and what exclusions apply. For most Wisconsin residents, the greater insurance concern is other hazards like severe storms, flooding, or winter weather, which are far more likely to cause damage.

Most earthquake-related losses in low-risk states like Wisconsin are actually from secondary causes, such as a fire following an earthquake or a gas leak. Ensuring your home has proper gas shut-off valves and working smoke detectors can help mitigate these risks. In addition, securing heavy furniture and appliances reduces the chance of injury and property damage from falling items, even during a minor earthquake.

How to prepare your home

Even though the risk is low, taking a few simple steps can make your home safer and more resilient. The following measures are recommended by Ready.gov and FEMA:

• Secure heavy furniture and appliances, such as bookcases, dressers, and water heaters, to wall studs using straps, brackets, or anchors.
• Fasten shelves securely to walls, and place large or heavy items on lower shelves.
• Store breakable items (e.g., glass, china) in closed cabinets with latches.
• Brace overhead light fixtures and ceiling fans to prevent them from falling.
• Repair defective electrical wiring and leaky gas connections, and consider installing flexible pipe fittings to reduce the risk of leaks during shaking.
• Know where your gas meter and main shut-off valve are and how to turn them off. Keep a wrench near the valve.
• Create a family emergency plan and practice 'Drop, Cover, and Hold On' drills.
• Assemble an emergency kit with water, non-perishable food, a flashlight, batteries, a first-aid kit, and important documents.
• Consider a professional inspection of your home's foundation and structural connections, especially if you own an older home with unreinforced masonry.
• Follow current building codes for new construction or major renovations; modern codes include seismic provisions that improve safety.

Frequently asked questions

Are earthquakes common in Wisconsin?

No. Wisconsin is in a region of very low seismic activity. According to the USGS, the state experiences only occasional small earthquakes, and most are too weak to be felt. The overall risk is rated Level 1 out of 5 by Wisconsin Emergency Management. While small earthquakes can happen, they are rare events and typically cause no damage.

Does homeowners insurance cover earthquake damage in Wisconsin?

Typically, no. Standard homeowners insurance policies exclude earthquake damage. You would need to purchase a separate earthquake policy or endorsement. However, given the very low risk in Wisconsin, many homeowners choose not to buy this coverage, and some insurers may not even offer it. Check with your insurance agent for details about your specific policy and what options are available.

What should I do during an earthquake in Wisconsin?

If you feel shaking, Drop, Cover, and Hold On. Drop to your hands and knees, take cover under a sturdy desk or table, and hold on until the shaking stops. If no shelter is nearby, cover your head and neck with your arms. Stay indoors until the shaking stops and it is safe to exit. If outdoors, move to an open area away from buildings, trees, and power lines. For more guidance, see Ready.gov.

Official resources

• Wisconsin Emergency Management – State agency for emergency preparedness and response.
• USGS Earthquake Hazards Program – Real-time earthquake information and hazard maps.
• Ready.gov – Earthquakes – Federal guidance on earthquake safety and preparedness.
• FEMA Earthquake Safety – FEMA's earthquake risk management resources.