Since growers had already begun harvesting and processing the grapes, the quake did more damage than if the grapes had still been hanging on the vine when it struck, although wineries would have suffered even greater losses if the harvest season had been further along.
"In another month, we would've had double the amount in barrels," said Liz Thach, a professor at Sonoma State University's Wine Business Institute.
"Some NVV [Napa Valley Vintners] member wineries did sustain damage to their barrel storage areas, wine inventory and production equipment over the weekend," the 500-member trade association said in a statement.
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Some experts think the final tally will be even higher. Taking into account residential losses along with wineries' loss of product, damaged facilities and canceled bookings from tourists, the quake could inflict losses as high as $4 billion, according to Kinetic Analysis Corporation data. Insurance is likely to cover only about $1.5 billion of that, "due to the (earthquake) insurance penetration figures in that area ... and the heavy impact of this event on contents (and) inventory," Kinetic CEO Steven Stichter said via email.
It's unknown what percentage of Napa's more than 500 wineries carry earthquake insurance, but it's likely a small number.
"We do know that fewer than 6 percent of homeowners in the Napa area have earthquake coverage and that take-ups rates across the state for this type of insurance have been declining for nearly 20 years," Insurance Information Institute president and economist Bob Hartwig said via email.
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