SEATTLE - In a study funded by the Homeland Security Department, Juneau was ranked the least vulnerable to terrorism in the United States.
Boise, Idaho, was the only Western city in the top 10 among 132 urban centers ranked by vulnerability based on a unique mathematical calculation.
The report, which relies on a complex formula for a "place-based vulnerabilities" score, first appeared in December in the journal Risk Analysis. Communities it identified have since been trying to absorb its meaning.
Scores depended on three main considerations: social demographics, natural hazards (floods, wildfires, earthquakes, extreme weather, etc.) and infrastructure vulnerability (roads, bridges, tunnels, ports, dams, skyscrapers, etc.).
Boise, it seems, faces high risk from extreme events such as wildfires or failure of a large dam upstream, Piegorsch said. Seventeen miles northeast of Boise, Lucky Peak Dam extends 2,340 feet long and 340 feet high. The 12-mile-long reservoir behind it stores 300,000 acre-feet of water.
"That dam could be a very likely target, or possible target," he said, noting that Boise's recent experience with disaster, flooding, property loss and casualties also elevated its rank.
The index says more about experience and ability to cope than about where terrorists might strike, Piegorsch said.
"You can't predict the next terrorism," he said. "That's why it's terrorism. But you can predict vulnerability."
Co-written by Susan L. Cutter at the University of South Carolina and Frank Hardisty at Pennsylvania State University, the research investigated relationships between vulnerability and terrorist outcome.
The project, four years in the making, crunched data from 1970 through 2004 related to natural or man-made disasters and hazardous events, including terrorism. The data boiled down to a single place-based vulnerability index.
The index borrowed from statistical methods used in research involving identifying cancer-causing substances. The National Cancer Institute funded part of the study.
Researchers assigned the cities threat-level color codes: green (low), yellow (medium) and red (high).
A swath of red cities stretched from Houston up to New York. Several cities in the Carolinas (Raleigh/Durham, Charlotte, Charleston and Columbia) were red.
Most cities in the West and North were yellow or green. Western localities, in general, covered more land. ("Once you sprawl, you lower vulnerability,." Piegorsch said. "You can't hit a less concentrated location as effectively.")
"San Francisco has had earthquakes, but emergency response has improved because of it," Piegorsch said.
Los Angeles and San Diego, both yellow, benefited from experience as well as being geographically spread out.