Stop Chasing the Big One: How We Actually Prepare for Earthquakes

You've heard it a thousand times: "When the big one hits..." But as someone who works in seismology, I'm here to tell you that's the wrong way to think about earthquake risk. The truth is, the earthquake that will likely affect you isn't a magnitude 9 off the coast—it's a magnitude 5 or 6 that ruptures right beneath your city. And while the media fixates on the 'big one,' we professionals focus on the everyday seismic reality. Here's how we actually prepare, and why you should too.

This guide is for anyone who lives in an earthquake-prone region—whether you're a homeowner, a renter, a business owner, or just someone who wants to be ready. We'll walk through the practical steps we take in the field, based on decades of seismic data and engineering principles. Forget the myths and the fear-mongering; this is the real deal.

1. Know Your Real Risk: It's Not the 'Big One'

First, we stop obsessing over the single largest possible earthquake and instead look at the actual seismic hazard in your area. The fact is, about 80 percent of the energy released in earthquakes comes from the Circum-Pacific Belt—the "Ring of Fire"—and another 15 percent from the Alpide Belt that runs through the Mediterranean and across Asia (Britannica / Earthquake). But even if you're not on those belts, smaller quakes can still cause significant damage if they strike near populated areas. Around 100 earthquakes each year are large enough to cause substantial damage if their centers are near habitation (Britannica / Earthquake). So, the first step is to check your local seismic hazard map—not a national map, but the one from your state or city geological survey. That map tells you the expected ground shaking for your specific location, not just a vague "high risk" label.

We also look at the type of fault. Is it a strike-slip fault like the San Andreas, or a subduction zone like in the Pacific Northwest? The shaking patterns differ, and so does the building code. Don't just ask "Will there be a big one?" Ask "What kind of shaking will my neighborhood experience?" That's the question that matters.

2. Secure Your Space: The Cheap, Effective Stuff

Once you know your risk, you move to the most cost-effective mitigation: securing your contents. We're not talking about bolting your house to the foundation yet—that's step four. First, we do a "furniture walkthrough." Walk through every room and ask: What could fall and hurt someone? What could fall and block an exit? What could fall and cause a fire (like a water heater)?

• Secure tall furniture (bookshelves, cabinets) to wall studs with brackets.
• Use earthquake putty or straps for TVs, monitors, and other heavy electronics.
• Install latches on kitchen cabinets to prevent dishes from flying out.
• Anchor heavy appliances like refrigerators and water heaters.

This is the stuff we do in our own homes first, because it's cheap, it's easy, and it saves lives. During a moderate quake, most injuries come from falling objects, not collapsing buildings. And don't forget the water heater—if it topples and breaks a gas line, you've got a fire hazard on top of the earthquake.

3. Drop, Cover, and Hold On: The Only Drill That Works

You've probably seen conflicting advice: stand in a doorway, run outside, or get under a table. We have a clear answer: Drop, Cover, and Hold On. This is the officially recommended response by emergency management agencies worldwide. It's not just a slogan; it's based on injury data from real earthquakes. When the ground shakes, you drop to your hands and knees, crawl to a sturdy table or desk, cover your head and neck with one arm, and hold on to the leg of the table with the other. If there's no table, drop next to an interior wall, away from windows, and cover your head with your arms.

Why not a doorway? In modern buildings, doorways are no stronger than any other part of the frame, and they're often swing and can slam shut on your fingers. Why not run outside? You're more likely to be hit by falling debris or glass as you run. The key is to be in a safe spot before the shaking gets violent. Practice this drill with your family, at work, and at school. Make it muscle memory.

4. Retrofit Your Home: The Big-Ticket Item That's Worth It

Now for the part that costs money. If you own a home, especially an older one, you need to consider a seismic retrofit. The two most common issues are: (1) an unbraced cripple wall (the short wall between the foundation and the first floor) and (2) an unanchored house (the house is not bolted to its foundation). In an earthquake, these weaknesses can cause the house to slide off its foundation or collapse. A professional contractor can add plywood bracing to cripple walls and install anchor bolts. This can cost a few thousand dollars, but it's the single most effective thing you can do to protect your home investment.

We also look at the chimney. Masonry chimneys are notorious for collapsing during earthquakes. If you have an unbraced chimney, consider having it reinforced or removed. And if you live in an area with liquefaction potential (where water-saturated soil behaves like a liquid), you might need a geotechnical engineer to assess your foundation. It's not glamorous, but it's what separates the prepared from the unprepared.

What can go wrong? You might think you can do the retrofit yourself, but unless you're a licensed structural engineer, don't. A botched retrofit can give you a false sense of security and may actually make your home more vulnerable. Also, beware of contractors who offer "earthquake-proofing" but don't follow the local building codes. Always get a permit and have the work inspected.

5. Prepare for the Aftermath: You're on Your Own for a While

After a big quake, emergency services will be overwhelmed. It could be days before help arrives. So, we prepare to be self-sufficient. That means having at least three days—preferably a week—of water and food for every person in your household. The fact base reminds us that groundwater is the vast majority of unfrozen fresh water, but that doesn't help you when pipes are broken. Store one gallon per person per day, plus food that doesn't require cooking. Don't forget a manual can opener, a first-aid kit, a flashlight with extra batteries, and a battery-powered or hand-crank radio.

We also plan our communication. In a disaster, cell towers may be down. You need a designated out-of-state contact person that everyone in your family can call to check in. And practice your evacuation route—both from your home and your neighborhood. Know where the gas shut-off valve is and how to turn it off (but only if you smell gas, because shutting it off requires a professional to turn it back on).

Finally, the most important thing to remember: the earthquake itself doesn't kill people; the built environment does. By securing your space, practicing the drill, retrofitting your home, and preparing for the aftermath, you're not just following a checklist—you're taking control of your safety. So stop worrying about the 'big one' and start taking action today.

Sources

• Britannica / Earthquake - https://www.britannica.com/science/earthquake-geology
• Britannica / Volcano - https://www.britannica.com/science/volcano
• NOAA NOS / Weather vs climate - https://oceanservice.noaa.gov/facts/weather_climate.html
• USGS / Groundwater - https://pubs.usgs.gov/publication/70170115