Earthquake swarm damages water lines and roads near Brawley, California
Hundreds of earthquakes struck the Brawley area of Imperial County, California, from May 9 to 11, 2026, including the strongest reported M4.7 event at 07:10 UTC on May 10. The swarm caused infrastructure damage, including water line breaks and road damage.
Earthquake swarm in Brawley, California - May 2026. Credit: TW/SAM, ESRI. Data source: USGS
More than 150 earthquakes were recorded during the earlier phase of the swarm, totaling close to 400 by 08:00 UTC on May 11. The sequence was centered near Brawley and the southern Salton Sea region within the Brawley Seismic Zone.
The M4.7 earthquake was registered at 07:10 UTC on May 10, at a depth of 14 km (8.7 miles), according to the USGS, which received nearly 200 reports of people who felt it. Shaking was felt across parts of Imperial County and elsewhere in Southern California.
Additional notable earthquakes reported during the sequence included an M4.5 at 03:39 UTC on May 10, an M4.4 at 02:22 UTC on May 10, and an M4.0 at 03:13 UTC on May 10.
About 180 000 people experienced light to strong shaking during the sequence, according to USGS estimates.
While local officials reported no major infrastructure damage or casualties, the earthquake swarm prompted emergency monitoring operations across Brawley and surrounding parts of Imperial County.
Residents were advised to inspect properties for possible water and gas leaks after repeated shaking, while local reporting described isolated water line issues, minor road damage, and limited utility-related impacts.
The City of Brawley activated its Emergency Operations Center as the California Governor’s Office of Emergency Services (Cal OES) coordinated assessments with local agencies.
Earthquake activity is somewhat slowing down today, according to USGS earthquake data, with the sequence shifting from clustered M3-M4 events during the earlier peak to lower-magnitude M1-M2 activity and no new M3+ earthquakes recorded through May 11.
The Brawley Seismic Zone regularly experiences swarm-type seismic activity, in which numerous earthquakes occur over a relatively short period without a single dominant mainshock. The tectonically active region lies between the southern San Andreas Fault system and the Imperial Fault.
References:
1 M 4.7 earthquake WSW of Brawley, CA – USGS – May 10, 2026
I'm a dedicated researcher, journalist, and editor at The Watchers. With over 20 years of experience in the media industry, I specialize in hard science news, focusing on extreme weather, seismic and volcanic activity, space weather, and astronomy, including near-Earth objects and planetary defense strategies. You can reach me at teo /at/ watchers.news.
Commenting rules and guidelines
We value the thoughts and opinions of our readers and welcome healthy discussions on our website. In order to maintain a respectful and positive community, we ask that all commenters follow these rules.