Why San Francisco Faces High Earthquake Risk

San Francisco sits at the boundary of two tectonic plates along the Pacific Ring of Fire. The San Andreas Fault runs directly through the Peninsula south of the city, while the Hayward Fault cuts through the East Bay a few miles to the east. The 1906 earthquake — estimated at magnitude 7.9 — destroyed most of San Francisco. The 1989 Loma Prieta earthquake (magnitude 6.9) killed 63 people and caused roughly $6 billion in damage.

The United States Geological Survey estimates a 72% probability of a magnitude 6.7 or larger earthquake striking the Bay Area before 2043. That is not a remote possibility for anyone who lives or works in the region. However, preparation dramatically reduces injury and death. Most earthquake casualties result from falling furniture, broken glass, and collapse of older unreinforced masonry buildings — all risks you can meaningfully reduce before any quake strikes.

Step 1: Secure Your Home Before a Quake

Retrofitting and securing your living space is the highest-impact action you can take before an earthquake. Work through this list room by room:

1. Anchor tall furniture to wall studs. Use L-brackets or anti-tip straps rated for at least 50 pounds. Secure bookshelves, dressers, filing cabinets, and wardrobes. Strapping kits cost under $20 at most hardware stores.
2. Strap your water heater. An unsecured water heater is both a fire and flood hazard after a quake. San Francisco code requires water heater strapping, but many older units are improperly installed. Use double-strap kits available at plumbing supply stores.
3. Install latches on kitchen cabinets. Magnetic push-to-open latches keep cabinet doors closed during shaking, preventing dishes and glassware from shattering onto floors where you will be walking after the quake.
4. Move heavy items to lower shelves. Heavy books, tools, and appliances positioned above shoulder height become projectiles during strong shaking. Rearrange storage so anything above chest level is lightweight.
5. Know how to shut off your gas. Locate your gas meter and keep a crescent wrench or dedicated gas shutoff tool nearby. Only turn off gas if you smell a leak — restoring service requires a utility technician visit.
6. Identify safe shelter spots in each room. In your bedroom, living room, and kitchen, identify where you would Drop, Cover, and Hold On: under a heavy desk, against an interior wall away from windows. Clear these zones of clutter today.

Step 2: Build Your Emergency Supply Kit

FEMA and the San Francisco Department of Emergency Management recommend storing enough supplies to be self-sufficient for at least 72 hours — and ideally up to two weeks, since a major quake can damage water mains, roads, and power grids for days before aid reaches all neighborhoods.

Water: Store 1 gallon per person per day. A household of two adults and one child needs at least 9 gallons for 72 hours. Use commercially sealed water bottles or BPA-free storage containers. Rotate every 6 to 12 months by using and replacing the oldest containers first.

Food: Stock non-perishable items that require no cooking: canned beans, tuna, crackers, peanut butter, granola bars, and dried fruit. Keep a manual can opener with the kit. Gas service may be shut off after a quake, so plan for cold-food options.

• First aid kit with bandages, antiseptic wipes, pain reliever, and a 30-day backup supply of any prescription medications
• Flashlights and extra batteries, or hand-crank flashlights
• N95 dust masks — one per person — for structural dust after nearby collapse
• Heavy work gloves for moving debris safely
• Copies of important documents in a waterproof bag: photo ID, insurance cards, lease or deed, and a written list of emergency contacts
• Cash in small bills — ATMs and card readers will be offline for days after a major quake
• A portable battery bank kept fully charged, with charging cables for your devices
• A whistle to signal rescuers if you become trapped under debris

Store the kit in a bag or hard-sided container near an exit. Avoid storing it in a garage that could be blocked or structurally compromised after a major quake.

Step 3: Create a Family Communication and Evacuation Plan

During a major earthquake, cell networks become overloaded and local voice calls frequently fail while long-distance calls and texts still go through. Building your plan before you need it takes less than an hour and can be the difference between reuniting quickly or spending hours searching for family members.

1. Designate an out-of-state contact. Every household member should memorize the name and phone number of one person outside California. After a quake, each family member contacts that person to check in; the out-of-state contact relays information to others looking for each other.
2. Establish two meeting points. Choose a spot near your home — the corner of your block, a neighbor’s driveway — for small emergencies. Choose a second spot farther away, such as a neighborhood park or library, if the immediate block is inaccessible.
3. Know your children’s school evacuation plan. San Francisco Unified School District has formal student reunification protocols. Know the designated pickup location for your child’s school, and bring photo ID — schools will not release students to unidentified adults during emergencies.
4. Sign up for AlertSF. San Francisco’s emergency notification system sends alerts by text or email for earthquakes, fires, and major emergencies across the city. Register through the SF.gov website.
5. Talk with your neighbors now. Know who on your block may need assistance evacuating — elderly residents, people with mobility limitations, households with infants. In any neighborhood-level disaster, neighbors are consistently the first to respond and the first to help.

Step 4: Drop, Cover, and Hold On When Shaking Starts

When shaking begins, you have seconds to act. The correct response — endorsed by the American Red Cross, USGS, and FEMA — is Drop, Cover, and Hold On. Running outside or standing in a doorway are both ineffective and dangerous in modern buildings.

1. DROP to your hands and knees immediately. This position keeps you stable and prevents you from being thrown off your feet by the strongest shaking waves.
2. COVER your head and neck with your arms. If a sturdy table or desk is within reach, crawl under it for additional protection. Stay away from windows, exterior walls, and anything overhead that could fall on you.
3. HOLD ON to your shelter and be prepared to move with it. Keep holding on until all shaking completely stops. Do not get up or move until the room is fully still.

If you are outdoors: Move away from buildings, utility wires, and streetlights. Once you are in the open, drop to the ground and wait for shaking to stop before moving toward any structure.

If you are in a car: Pull over away from bridges, overpasses, and utility lines. Stay inside with your seatbelt on. After shaking stops, check for road damage and proceed slowly.

Never run outside during shaking. The majority of earthquake injuries occur when people try to move during the event and are struck by falling debris near exits. Doorframes in modern wood-framed and steel buildings offer no special structural protection — this is a persistent myth from an era of adobe construction.

Step 5: What to Do Immediately After an Earthquake

The minutes and hours following a major earthquake are critical for safety and recovery. Work through this checklist once shaking fully stops:

1. Check yourself and others for injuries. Do not move seriously injured people unless they are in immediate life-threatening danger. Apply first aid if you are trained, and call 911 when lines are available.
2. Expect aftershocks. Aftershocks can strike within seconds or hours of the main quake and may be strong enough to cause additional structural damage. Remain ready to Drop, Cover, and Hold On again at any time.
3. Check for gas leaks. If you smell gas, open windows, leave the building immediately, and call PG&E at 1-800-743-5000 from outside. Do not use light switches, lighters, or any open flame. Do not return until a utility technician clears the building.
4. Inspect for structural damage before re-entering any building. Look for large cracks in foundations or load-bearing walls, visible tilting, or debris blocking exits. If a building appears damaged, stay outside and contact the San Francisco Department of Building Inspection.
5. Use text messages, not voice calls. Texts require far less network bandwidth and are much more likely to get through on overloaded cell networks. Send a text to your out-of-state contact first, then reach other household members.
6. Avoid elevators. Structural shifts can jam elevator doors and shafts. Use stairs only after confirming they are intact and clear of debris.
7. Tune to emergency radio. A battery-powered or hand-crank radio lets you receive official guidance if power and cell service are both down. KCBS 740 AM and KQED 88.5 FM serve as San Francisco’s primary emergency broadcast stations.

Earthquake Apps and Resources for SF Residents

San Francisco and California offer several official tools to help residents prepare and respond effectively before and after a quake:

• MyShake (UC Berkeley): A free mobile app that uses the ShakeAlert early warning system to send alerts seconds before shaking reaches your location — enough time to Drop, Cover, and Hold On before the strongest waves arrive. Available on iOS and Android.
• AlertSF: San Francisco’s official emergency notification system. Register at SF.gov to receive city-issued alerts by text or email for earthquakes, fires, and other major emergencies across the city.
• SF72: San Francisco’s official preparedness resource with downloadable checklists for supplies, evacuation plans, and neighborhood-specific information, available in multiple languages through the SF.gov emergency management pages.
• USGS Earthquake Hazards Program: Real-time earthquake maps, magnitude updates, and shake maps showing ground motion intensity for any recent earthquake across the Bay Area. Visit earthquake.usgs.gov to check activity after any tremor.
• Nextdoor: Many San Francisco neighborhoods use Nextdoor for real-time neighbor-to-neighbor communication during local emergencies. Set up an account and join your neighborhood group now, well before you need it.

The San Francisco Fire Department’s NERT program — Neighborhood Emergency Response Team — offers free training to residents who want to support their communities during a major disaster. Courses cover first aid, light search and rescue, fire suppression, and basic triage. Registration is available through the San Francisco Fire Department’s website. Completing NERT training turns your preparedness from personal to neighborhood-wide, which is where it matters most when emergency services are stretched thin after a large quake.