Magnitude 3.5 Earthquake Strikes San Bernardino County, California

San Bernardino, California – A magnitude 3.5 earthquake struck San Bernardino County on Tuesday, August 5, 2025, at 4:54 PM local time. The U.S. Geological Survey (USGS) reported the earthquake’s epicenter was located 3.8 miles from Rialto and 4.5 miles from Fontana, in a region known as Inland Empire.

Residents throughout the area felt the tremor, with reports coming from Rialto, Fontana, and nearby communities such as San Bernardino, Muscoy, and Rancho Cucamonga. The quake was even felt in more distant locations, including Orange County, Santa Clarita, and Temecula.

Over the last 24 hours, a total of 19 earthquakes of magnitude greater than 2.5 have been recorded in North America and the Caribbean. Of these, 11 occurred within the continental United States. The strongest was a 4.0 magnitude tremor located six kilometers from Brawley, California.

The San Andreas Fault runs approximately 1,300 kilometers through California and marks the boundary between the Pacific and North American tectonic plates. It has drawn the attention of scientists studying the potential for a catastrophic earthquake referred to as the Big One. This anticipated quake could be of magnitude 8 or higher, potentially causing widespread destruction, especially in densely populated urban areas like Los Angeles and San Francisco.

Historical records show that significant earthquakes termed as Big Ones struck California previously, including one measuring 7.8 in 1906 and another measuring 7.9 in 1857, according to USGS data.

In preparation for the possibility of future major earthquakes, authorities regularly conduct drills, review safety measures, and promote public awareness about earthquake preparedness.