The Northridge Earthquake, a 6.7 magnitude quake that was the costliest earthquake disaster in the history of the United States, rocked the Santa Clarita Valley 30 years ago on Jan. 17, 1994.

The tembler stuck at at 4:30:55 a.m. on a Monday, the Martin Luther King, Jr Day federal holiday, when most people were asleep.

The quake lasted approximately 10–20 seconds and its peak ground acceleration of 1.82 g was the highest ever instrumentally recorded in an urban area in North America. The peak ground velocity at the Rinaldi Receiving Station was 183 cm/s (4.1 mph; 6.6 km/h), the fastest ever recorded.

The earthquake, with an epicenter in the San Fernando Valley, was felt as far away as San Diego, Las Vegas, Phoenix and Ensenada.

Despite being named the Northridge Earthquake, the quake’s epicenter was actually in Reseda.

Two 6.0 Mw  aftershocks followed the 6.7 quake, the first about one minute after the initial event and the second approximately 11 hours later. The earthquake generated several thousand aftershocks in the weeks following the quake.

The quake damaged or destroyed more than 40,000 structures in Southern California, resulting in $20 billion in damage and costing an estimated $42 billion in economic loss.

Throughout the Santa Clarita Valley mobile homes were knocked from their foundations and 14 mobiles homes in the Greenbrier Mobile Home Park in Canyon Country off Soledad Canyon Road burned to the ground.

Santa Clarita City Hall was deemed unsafe to inhabit and power was out for nearly 24 hours. Telephone service was disrupted and people spent hours cleaning up broken glass and items thrown from shelves throughout the SCV.

The collapse of the I-5/14 interchange isolated the SCV for months after the quake.

The I-5 freeway opened four months after the earthquake struck, 33 days ahead of schedule. Southbound lanes were opened on May 17, and the northbound lanes on May 18.

The lanes connecting the I-5 and State route 14 were not reopened until July, 1994.

The death toll from the Northridge quake, origianlly pegged at 57 people, then 61, is now estimated by some sources at 72, including heart attacks, 33 people died from fallen buildings. Of those 33 people, 16 were killed when the 164-unit Northridge Meadows apartments collapsed.

Two people died in the SCV, one from a heart attack. Los Angeles Police Department Officer Clarence Dean was killed when his motorcycle drove off of a section of the Antelope Valley Freeway in the Newhall Pass which had collapsed due to the Northridge earthquake.

Resulting legislation because of lessons learned from the earthquake required the retrofit of many buildings in Los Angeles County and the state legislature passed a law requiring all hospitals in California to ensure that their acute care units and emergency rooms would be in earthquake-resistant buildings by Jan. 1, 2005.