It was at 7:42 a.m. on October 1, 1987, that a strong earthquake measuring M5.8 rocked the east Los Angeles region. The Whittier Narrows earthquake shook the region quite hard, registering shaking intensities of VIII on the Modified Mercalli intensity scale (a relative shaking intensity scale from 1-12 shown in Roman Numerals).

The temblor was centered between Whittier and Montebello along the west-northwest trending Whittier fault zone and was felt as far away as Las Vegas. No surface fault ruptures were ever discovered. Eight people were killed and many were injured.

The quake damaged more than 10,400 buildings and the total cost of property damage exceeded $350 million. Felt aftershocks lasted for months and microearthquakes were recorded for years.

The quake underscored to engineers, planners, and policy makers that even events registering less than M6 can cause significant damage, and even death, if they centered in densely populated areas.

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