Back to back earthquakes rattle San Jose

Two earthquakes rattled the San Jose area late Tuesday night, causing no significant damage but at least vividly illustrating the necessity of disaster prep.

At 7:19 p.m. on Tuesday evening the US Gelogical Survey recorded a magnitude 3.1 quake near San Martin in Santa Clara County, north of Gilroy and south of Morgan Hill, raising alarms and blood pressure but doing little else by way of significant damage.

Then about three hours later a magnitude 3.9 quake went off just east of the Alum Rock neighborhood in San Jose. CBS SF reports that, again, no one in Santa Clara County reported significant property damage or injury, although the much bigger tremor—a 3.9 shake releases more than 15.8 times the energy of a 3.1—raised hackle as far away as Marin County, according to USGS.

When push comes to shove, a couple of sub-4.0 movements along the Calaveras Fault is nothing to write home about in the earthquake-prone Bay Area. But it is yet another timely reminder that the region’s geological clock never stops ticking and residents should prepare.

In 2010, a California Emergency Management Agency survey found that 40 percent of people in the state didn’t know what kind of supplies they should have on hand in case the Big One comes. Fewer than 20 percent had retrofitted or inspected their homes for seismic resistance. Some 60 percent did not have a disaster plan or potable water on hand.

Photo by Justin Sullivan/Getty Images

Ideally, the Department of Homeland Security advises households have one gallon of water per person per day less than six months old and stored in plastic containers, plus canned foods and dry goods to last for at least three days without assistance.

A first aid kit, battery-powered lights and radio with batteries, and basic tools like a can opener, matches, and disposable dishes. Since banks will likely close and electronic services may be unavailable, DHS recommends keeping cash or traveler’s checks on hand.

Not every household can afford to stockpile basic supplies or resources just in case, but everyone in the Bay Area should take whatever steps possible to prepare within their budget. Because the problem definitely isn’t going away.

• San Martin Earthquake [USGS]
• Alum Rock Earthquake [USGS]
• Earthquakes Strikes East San Jose [CBS SF]
• Quake Preparedness Survey [Cal OEM]
• Built a Kit [DHS]