Dr. Levitan raises several important issues regarding the risk exposure of chemical plants to hurricane and other extreme winds. Perhaps the more important point is that, as a whole, most chemical plants along the Texas, Louisiana, and lower Mississippi River have not experienced a strong Category 3 or greater hurricane, with sustained wind speeds in excess of 125 mph, during their lifetimes. For example, from 1900 through 1932, two Category 4 hurricanes (1915, 1932) and one Category 5 hurricane (1900) made landfall along the shorelines of Galveston County and Brazoria County in Texas. These catastrophic storms appeared before construction of a majority of chemical plants in this region had occurred. The last major hurricane to strike the region, Hurricane Alicia in 1983, produced winds of up to 110 mph along the Houston Ship Channel. Damage occurred to plants, but it was not widely reported. Interestingly, the 1943 Hurricane (a Category 2 storm) that passed through Galveston Bay caused enough damage to interrupt aviation fuel supplies during World War II (the damage was kept secret for several years for national security reasons).

Not only is wind a concern, but flooding associated with these storms is a major issue, too. A 12-ft storm surge, produced by Hurricane Georges last year, flowed over the existing 9-ft levee of a major refinery along the Mississippi coast. The wind and flood damage, coupled with business interruption costs, was in the hundreds of millions of dollars.

Earlier this year EQE conducted a wind risk survey among its petrochemical and refinery clients. Sixty-five percent of respondents had high confidence in the ability of their physical plant to withstand an extreme wind. However, an equal percentage of respondents are either very concerned or somewhat concerned about their potential vulnerability to hurricane and tornado winds when compared to other catastrophic events. Given this apparent dichotomy, perhaps a false sense of security does exist.

Bob Bailey
Wind Engineering Services
EQE International - Houston