04/01/2008 -A newstudy, which ranks cities by their vulnerability to terrorism, identified Boise, Idaho, as the most assailable city by terrorists in the Western United States,reports the Los Angeles Times.

Boise came in 10th place behind the top five most vulnerable cities: New Yok City-Newark; New Orleans, Louisiana; Baton Rouge, Louisiana; Norfolk, Virginia; and Charleston, South Carolina—all port cities.

The study, funded by the Department of Homeland Security, has shocked local authorities. Charles McClure, spokesman for the Boise Police Department, said the department can't understand how its city ranked so high.

Boise is a landlocked city with a population of 200,000 that ranks high on many quality of life indexes.

However, the study's methodology and Boise's surrounding terrain combined to elevate its calculated vulnerability.

The report, which relies on a complex formula for a "place-based vulnerabilities" score, first appeared in December in the journal Risk Analysis .... 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, [Walter W.] Piegorsch [a mathematics professor at the University of Arizona] 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.

One of the study's authors, Piegorsch said the dam could be a major terrorist target.

The study divided a city's vulnerability to terrorism into three categories: green (low), yellow (medium), and red (high). Red splashed most conspicuously along the East Coast, while the West Coast did not furnish one city in the red.

Cities like Los Angeles and San Francisco, presumed to be more vulnerable to terrorist attacks, had mitigating factors, resulting in a medium level of vulnerability. One major factor contributing to Los Angeles yellow designation is the city's spread out nature, while San Francisco's yellow mark has to do with its experience with natural disasters, which led to better building practices and preparedness measures.

Responding to the question whether the study's results should be public, Piegorsch said "the bad guys have figured this out already," so its better to understand where the nation is vulnerable to attack and respond effectively.

A spokesman for Idaho's Department of Homeland Security said state officials are working with the FBI and the study's authors to improve their preparedness in case tragedy strikes.