Earthquake

Morrow, Joshua. (2004, May/June). 2003 San Simeon Earthquake - Lessons learned on the faultline. Practical Winery and Vineyard, pp. 78-82.

This paper by a consulting structural engineer examined the impact, on wineries, of the December 22, 2003 earthquake of magnitude 6.5 that struck central California. The region struck had a low population density but a relatively high density of wineries.

While no deaths were reported in any winery one employee, at one winery, operating a forklift at the time was saved by her forklift's robust steel rollover cage protecting her from a collapsing stack of barrels.

There were no building failures. The greatest amount of financial loss was due to toppled and damaged wine barrels. In many wineries stacks of barrels on two barrel racks collapsed due to rack walking and sliding. Stacks of all different heights collapsed due to these phenomena. Wine loss was greatest in higher stacks due to the barrels falling from a great height. Tight stacking of barrels provided no more protection than loosely stacked barrels.

Barrels chocked in a three high pyramid configurations collapsed due to the chocks working loose.

Wine loss was minimised in one winery where the building's walls restrained the falling barrels. Buildings should be designed with sufficient strength to withstand barrel stacks leaning against the walls.

The author suggests that wineries should have one or more prebuilt forkliftable safety cages located in high risk areas where staff can take shelter from falling barrels in the event of a major earthquake.

All barrel rooms should have adequate exits as some may be blocked by fallen barrels.

Stainless-steel wine tanks were discussed. Current US tank design codes do not require seismic design in high seismic zones. In addition the anchors provided on preinstalled tanks are not generally designed for earthquakes. In the event of an earthquake they may either fracture or tear the tank at the base releasing the contents.

It was found that shrink-wrapped palletised cases of wine sustained very little damage. The shrink-wrap was remarkably effective in confining the cases of wine.

A significant number of wineries sustained damage in the tasting rooms and also in their wine libraries. Hospitality personnel should have proper emergency response training.

The paper discusses the need for a winery response plan. It also points out that in the event of a major earthquake that personnel will tend to be more interested in the welfare of their family and home than in their place of work.