In some cases, steps taken to reduce the impact of natural hazards may actually make the situation worse when more extreme disasters occur, said Dennis Mileti, who led the study team of 132 experts.

The five-year, $750,000 study - titled Disasters by Design: A Reassessment of Natural Hazards in the United States - was funded primarily by the National Science Foundation's [NSF] Engineering Directorate. The Federal Emergency Management Agency [FEMA], the U.S. Geological Survey [USGS], the U.S. Forest Service and the Environmental Protection Agency [EPA] also contributed funding.

The study team was asked to evaluate what is known about natural hazards and come up with ways to reduce their social and economic costs. Mileti chairs the sociology department and directs the Natural Hazards Research and Applications Information Center at the University of Colorado at Boulder. He noted that seven of the 10 most costly U.S. disasters occurred between 1989 and 1994. The states of California, Texas and Florida experienced the greatest losses from natural hazards during the study period from 1975 to 1994.

The 1994 Northridge earthquake in California was the most costly natural disaster in U.S. history, at more than $25 billion. Japan's 1995 Kobe earthquake was the world's most expensive disaster, at $100 billion.

"The really big catastrophes are getting larger and will continue to get larger, partly because of things we've done in the past to reduce risk," Mileti said. "For example, building a dam or levee may protect a community from the small- and medium-sized floods the structures were designed to handle. But additional development that occurs because of this protection will mean even greater losses during a big flood that causes the dam or levee to fail. Many of the accepted methods for coping with hazards have been based on the idea that people can use technology to control nature to make them safe," he added.

The report, published by Joseph Henry Press of Washington, D.C., urges community leaders to "design future disasters" for their communities, actually setting the number of deaths and injuries and dollar losses they are willing to accept - and take responsibility for - as the result of the most extreme disasters their community could face during the next 100 to 200 years.

Mileti said, "We need to change the culture to think about designing communities for our great grandchildren's children's children."

Note: If no author is given, the source is cited instead.

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