Quake Toll Could Reach $15 Million

Damage from Sunday’s magnitude 5.2 Napa Valley earthquake could reach $15 million, with as many as 200 buildings requiring repair, Napa County authorities said Monday.

Meanwhile, the most seriously injured victim of the quake, 5-year-old Nathan Schank, was reported in “stable but very critical condition” by doctors at Oakland’s Children’s Hospital on Monday afternoon. The Napa youngster, one of 40 people injured in the temblor, suffered a broken pelvis, arm and shoulder.

New shake maps issued Monday by the U.S. Geological Survey showed that ground acceleration in the quake, the most destructive in California since the 1994 Northridge disaster, reached 40% of the force of gravity.

The quake’s fairly high intensity in terms of peak acceleration explains the substantial damage and injuries that occurred, although it was hardly comparable to the Northridge jolt, which had a peak intensity of 182% of gravity.

As authorities inspected more buildings in and near the cities of Napa and Yountville, one Napa apartment house was temporarily deemed unsafe, and its 71 residents, including 23 children, were sent to a church in Napa for shelter. Later, they were allowed to return.

Schank was sleeping in his parents’ house when he was struck by three 40- to 50-pound blocks that fell off the fireplace when the quake struck at 1:36 a.m.

A similar incident caused the only fatality in the 1992 Landers earthquake in Southern California, to a small child who was also sleeping next to a fireplace.

Besides Schank, the only other victim of Sunday’s quake who remained hospitalized was an unidentified woman with a broken hip. Others suffered minor cuts, bruises and fractures.

The number of aftershocks from the quake have remained low. After four on Sunday, only two more were reported by Monday evening. Both were 2.4 magnitude.

The earthquake caused more injuries than any in California since the magnitude 6.7 Northridge temblor. That quake caused 57 deaths and 11,000 injuries.

Scientists with the Geological Survey released historic seismicity maps for the area of Sunday’s quake, 40 miles northeast of San Francisco, and they confirmed that the epicenter was at least 12 miles away from the sites of past quakes of magnitude 5 and higher.

Some earthquake scientists say new quakes are prone to occur in gaps between previous quakes. The site of Sunday’s quake was in between past quakes in the magnitude 5 range.

The new quake was at least 3 miles from any previously known fault, scientists said.

Most of the Napa Valley’s famous wineries are to the north of the epicenter and were not badly damaged. Most of the reported damage was south of the epicenter, indicating the rupture was directed away from the wineries.

Less than two months ago, a simulated earthquake at UC Berkeley’s Pacific Earthquake Engineering Research Center was directed at testing how stacked wine barrels would fare in a temblor of magnitude 7.4.

During the simulation, 60-gallon wine barrels donated by the Robert Mondavi Winery and filled with water came tumbling down, and many burst, alarming winery observers invited for the occasion.

A quake of that magnitude would have been more than 100 times more powerful than Sunday’s Napa Valley quake.