At 4:31 a.m. on January 17, 1994, a 6.7-magnitude quake struck the San Fernando Valley, a densely populated area of Los Angeles located 20 miles northwest of the city’s downtown. The quake was caused by the sudden rupture of a previously undocumented blind thrust fault. The Northridge quake, named after the San Fernando Valley community near its epicenter, was the costliest in U.S. history, with damages estimated at more than $20 billion, and resulted in 57 deaths

Northridge Earthquake: January 17, 1994

Damage was widespread, as buildings, shopping centers, parking lots and portions of major freeways all collapsed. At least 57 people perished, while thousands more were injured. At the Northridge Meadows apartment complex, 16 people were killed, all of whom lived on the first floor, when the three-story, stucco-and-wood structure fell down on them. A motorcycle police officer died when his vehicle plunged off of a just-collapsed section of freeway.

Did you know? Southern California has about 10,000 earthquakes every year, although most are so small they aren’t felt.

The fact that the quake occurred on a federal holiday (Martin Luther King Jr. Day) and in the early morning hours when most people were home in bed was critical in reducing the number of casualties. Another important factor was that the building and safety codes in Los Angeles had been strengthened following a powerful quake in the San Fernando Valley in 1971 (also called the Sylmar Earthquake).

Northridge Earthquake: Aftermath

Following the Northridge disaster, which was responsible for estimated damages in excess of $20 billion, the majority of insurance companies representing homeowners in California severely restricted–or completely stopped offering—new policies because the law required them to also offer earthquake coverage. In response, the state created the California Earthquake Authority as a publicly managed, primarily privately funded organization providing basic residential earthquake coverage.