Rose Canyon Fault map
Map shows the location of the Rose Canyon Fault and areas that would be impacted by a major earthquake. Courtesy EERI

A new report finds that the long-dormant Rose Canyon Fault could produce a massive earthquake in San Diego that would kill hundreds of people and cause billions of dollars in property damage.

The local chapter of the Earthquake Engineering Research Institute said in the study released Wednesday that San Diego County faces an 18% probability of a temblor of 6.7 magnitude or greater over the next 30 years along the fault, which stretches from La Jolla through downtown San Diego and across Coronado.

The report studied the potential impact of a 6.9-magnitude quake centered off Del Mar and found it would kill 800 people, damage 120,000 buildings, likely shut Interstate 5 and the Coronado Bridge, cut many utility lines and displace 36,000 households. Property losses would total $38 billion.

“The region’s large population coupled with the poor seismic resistance of its older buildings and infrastructure systems, make San Diego vulnerable to earthquakes,” the report warned.

UC San Diego researches first warned in 2017 that the fault was more dangerous that previously thought, though there has not been a major quake along it since 1862, when the Pt. Loma lighthouse and buildings in Old Town were damaged.

The authors outlined a series of steps to increase the San Diego region’s resilience to a major earthquake.

“This report intends to paint a broad picture of the regional seismic risk profile to highlight the threat of the Rose Canyon Fault Zone and the many opportunities for earthquake mitigation to make the San Diego region more resilient to seismic hazards,” according to the report.

The Oakland-based Earthquake Engineering Research Institute is a nonprofit professional organization dedicated to reducing earthquake risk.

Chris Jennewein is Editor & Publisher of Times of San Diego.