A 6.0 earthquake shook Sonoma Valley at 3:20 a.m. Sunday.

A preliminary indication from the USGS showed that it was centered 4.2 miles northwest of American Canyon in Napa County.

Fire alarms were going off all over the Valley. Power went off momentarily, but came back on immediately in Agua Caliente. Power was off, with the exception of the stoplights, south of Fetters Avenue all the way through Sonoma.

Sonoma Valley Fire and Rescue Authority Division Chief Bob Norrbom said the department had been responding to fire alarms that went off and to some medical runs, but he hadn't heard of anything major. Sonoma Valley, Schell-Vista and Glen Ellen fire departments sent water tankers to Napa County because of the number of broken water mains there.

According to the City of Sonoma, Sonoma police and fire are not reporting any significant damage or injuries at this time. Public Works reports water system has not sustained any damage and is operational.

Sonoma Valley School Superintendent Louann Carlomagno reported that all schools have been checked and are secure. Schools will be open on Monday.

In a statement from Peter Rumble, with Sonoma County, there are no identified disruption to services in Sonoma County at this time as a result of the American Canyon Earthquake. No personal injuries have been reported in Sonoma County; there have been reports of minor property damage.

The County Emergency Operations Center opened early this morning, and County building and water officials were dispatched immediately following the earthquake to inspect facilities, roadways, and infrastructure throughout the county to assess any damages. Emergency responders and county officials are coordinating with Napa County, state officials, and the Sonoma Raceway.

Sonoma County responded to a request for aid at approximately 5:45 a.m. Sunday, providing 10 fire engines and one ambulance to Napa County. Pacific Gas and Electric has restored power services to several thousand customers, with approximately 640 customers in Sonoma County remaining without power.

Workers at Sonoma Market, which has an emergency generator, were busy cleaning up the debris shortly after the quake. The market was a lone beacon of light in the Sonoma darkness. Sonoma Market owner Dale Downing said the store lost a lot of wine as things flew into the aisles.

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