Seismo Blog

Today in Earthquake History: Northridge 1994

Categories:   Southern California  |  Blind Thrust Fault  |  Today in Earthquake History  | 

January 17, 2009  (The earthquake of 17-Jan-1994)

Is your water heater properly strapped to the wall? Do you have additional insurance on your house with the California Earthquake Agency (CEA)? If so, then you can thank a horrible event, which happened 15 years ago today in Southern California.

It was about 4:30 am when Clarence Dean was rudely awakened in his home in Lancaster in northern Los Angeles County. A major earthquake had shaken his house badly. He got up, dressed quickly and then jumped onto his Kawasaki Police 1000 motorcycle. Dean was an LA motorcycle cop, and this Martin Luther King Day would have been his day off. But he knew he would be needed at his Van Nuys police station because of the earthquake. From his home, it took him only a couple of minutes until he reached Highway 14. There he took the westbound direction and sped towards LA, the blue emergency strobe flashing on his bike. But he never made it to his assigned post. The swooping viaduct where Highway 14 meets Interstate 5 had collapsed in the quake. Where two lanes of concrete had been built in a gentle arc high above the ground, there was nothing left. In the darkness, Officer Dean spotted the gap too late and flew 75 feet through the air before crashing, 30 feet below, in a cascade of sparks and screaming metal.

Damage from the Northridge earthquake

Damage from the Northridge earthquake (Photo courtesy of M. Celebi, USGS)

The policeman was one of 72 people who died on that morning in a 6.7 quake, with a hypocenter 10 miles beneath the town of Reseda in the San Fernando Valley. Had it not been a federal holiday, many more people might have died during the early morning commute. Besides the 5/14 interchange, the Santa Monica Freeway (I 10) had collapsed near Cienega Boulevard, making this major artery unusable for weeks. Most of the damage, however, occurred in the town of Northridge, hence the name for this costliest temblor in US history. Homes, apartment buildings and even hospitals collapsed all over the San Fernando Valley. It was later estimated that the quake had caused more than $20 billion worth of damage. As a consequence, many insurers of private homes stopped offering protection against earthquakes in our state.

The same region had been the victim of a similarly damaging temblor 23 years earlier, the San Fernando earthquake of 1971. Seismologists later found out that these two quakes occurred on two different, previously unknown faults. After the Northridge quake, the California Legislature passed several laws in a rare form of bipartisan unity. One gave life to CEA, which now underwrites earthquake insurance statewide. The building code was also amended, requiring each newly installed gas-powered water heater to be strapped to the wall. Too many heaters had fallen on that fateful morning 15 years ago, breaking the gaslines and causing devastating fires. (hra028)