Understanding US Earthquake Risk
The United States experiences significant seismic activity, with major earthquake zones concentrated along the Pacific Coast and in the Interior West. The U.S. Geological Survey (USGS) estimates that over 1,500 earthquakes occur annually in the country, though most are minor.
High-Risk Zones
California remains the most seismically active state, accounting for approximately 80% of the nation's earthquakes. The San Andreas Fault System is responsible for major seismic events, with a 72% probability of a magnitude 6.7+ earthquake in California within the next 20 years. The Pacific Northwest, particularly around the Cascadia Subduction Zone, poses a significant long-term threat comparable to Japan's major fault lines.
Economic Impact
Annual earthquake losses in the US average $5.8 billion. The 1906 San Francisco earthquake caused an estimated $235 million in damage (equivalent to $8 billion today). Modern building codes have improved resilience, but older structures remain vulnerable.
Risk Mitigation
Most at-risk states have implemented seismic building codes and early warning systems. Earthquake insurance is available but covers only about 10% of California properties, leaving significant financial exposure.