The rural expanse of Mendocino County in Northern California experienced its most powerful earthquake in nearly nine decades on Wednesday morning. The 5.6-magnitude quake centered about 7 miles northwest of the agricultural town of Willits sent shockwaves through the region, causing injuries and widespread power outages.
The U.S. Geological Survey (USGS) reported that the quake struck at 8:10 a.m. PT, with its epicenter located approximately 5 miles deep. The tremor was felt as far as the coastal city of Fort Bragg some 50 miles west of the epicenter. This seismic event marks the strongest quake in the region since 1940, according to veteran seismologist Lucy Jones.
Impact on Communities and Infrastructure
The earthquake’s impact was immediate and far-reaching. Over 6,000 residents in six towns near the epicenter were left without power, as reported by the Mendocino County Executive Office. Authorities urged residents to stay off the roads to facilitate damage assessment and repair efforts.
In Calpella a town about 10 miles south of the epicenter, Brie Leon and her colleagues at Club Calpella Restaurant experienced the quake firsthand. “It almost felt like something hit the building,” Leon recalled. The quake knocked frames off the walls and bottles off the shelves, causing a significant mess that took hours to clean up.
Meanwhile, in Kelseyville about 40 miles southeast of the epicenter, Alan Harris and his family received an earthquake alert on their cellphone just moments before the house began shaking. “It was scary. You could hear things crashing, mostly on the third floor of the house,” Harris said. Despite the intensity, no major structural damage was reported.
Earthquake Early Warning System in Action
The California Governor’s Office of Emergency Services reported that nearly 657,000 earthquake early warning alerts were sent via the MyShake App throughout Northern California. The ShakeAlert Earthquake Early Warning System played a crucial role in alerting residents, providing them with precious seconds to prepare.
Robert de Groot a scientist with the ShakeAlert operations team explained that the system uses ground and satellite sensors to detect fault movement in real time. “The alert deliveries for this are going to be well over a million,” de Groot said, highlighting the system’s effectiveness in reaching a wide audience.
The earthquake early warning system is designed to react to the faster-moving P-waves giving people a head start before the more damaging S-waves arrive. However, those closest to the epicenter may feel the quake before receiving an alert due to the physical limitations of seismic wave propagation.
Assessing the Damage and Aftershocks
Initial assessments revealed minor damage, including broken windows, ripped storefront awnings, and goods falling off shelves. State Sen. Mike McGuire who represents the affected district, reported that early inspections found no major damage to hospitals, water systems, or other public facilities in Ukiah and Willits.
The USGS measured the quake at a magnitude of 5.6, a level strong enough to be widely felt and capable of causing minor damage. The agency noted that the information is preliminary and could change as scientists review additional data. Aftershocks are likely, but experts expect them to be relatively minor.
In the aftermath of the quake, the Mendocino County Sheriff’s Office activated its Emergency Operations Center to monitor the situation. Residents were encouraged to report any property damage using a provided assessment form. The Willits City ManagerJames Connor coordinated with Pacific Gas & Electric Co. and the local fire department to address downed power lines and ensure public safety.
As the region continues to assess the impact of this significant seismic event, residents are reminded of the importance of preparedness and the valuable role of early warning systems in mitigating the effects of earthquakes.
