Assessing the Risk to Rail and Transit Systems: Considering All Hazards, Terrorist and Natural, Spreading Resources, and Addressing Common Risks Is the Best Approach

Article excerpt

On the morning of March 11, 2004, when bombs exploded in the Madrid train station, the security of America's rail and mass transit systems became of greater concern than the day before. In July 2005, Americans were reminded of the vulnerabilities of transit systems when bombs exploded in the London Underground. However, rail and transit security has not become a national priority. Following the 9/11 attacks on the World Trade Center and Pentagon--and the 9/11 Commission's recommendation of increased attention to the risks--discussion has been considerable concerning the vulnerability of the nation's rail and transit systems, but little has been done to improve the situation.

The Madrid and London bombings reminded Americans of the dangers, and the perception of heightened risk did force the U.S. Department of Homeland Security (DHS) and other federal agencies, as well as rail companies and transit authorities, to invest more in system security. However, investments have been small, and rail and transit security clearly is not a priority. The Bush administration has asked for only $37 million for railroad and transit security for FY09, compared with $6 billion for aviation security. The issue was raised by Senator Barack Obama in his presidential campaign (www, and presumably he will address this vulnerability as president. The issue is not likely to be addressed soon, however. The questions that have to be answered now are (1) how high the risk is and (2) how it can be reduced to an acceptable level.

Need for Better Risk Management

Officials at all levels have recognized the need for better risk management to set policy priorities and guide resource allocations. The working group that developed The Principles of Emergency Management in 2007 listed "risk-driven" as one of the eight core principles in the profession and practice of emergency management. That principle reflects the concern among many professional emergency managers that homeland security priorities and federal funding too often do not address real, measurable risks in their communities. The U.S. Government Accountability Office (GAO), too, has expressed concern that homeland security programs lack effective risk management approaches. An expert panel convened by GAO determined that poor risk communication, politics, and a "lack of strategic thinking" inhibit the use of risk management.

Terrorism presents some challenge in terms of the measurement of risk. Risk assessment techniques usually focus on the frequency or probability of undesirable events and their likely severity. When there is a history of events, the frequency and intensity of future disasters can be extrapolated. For example, volcanic eruptions tend to follow cycles, with major events from a few decades to tens of thousands of years apart. The eruptions are largely effusive (characterized by lava flows) or explosive (characterized by explosions of ash, rock, and gas and by pyroclastic flows). Scientists can estimate how frequently a volcano will erupt and the likelihood that the eruption will be of one type or the other. Some new predictive models estimate the time and severity of eruptions, and warnings have provided time to evacuate threatened populations.

Terrorist events, while cyclic, are less amenable to estimation. However, terrorist organizations tend to have limited repertoires and resources, and predicting their future behavior on the basis of the past is reasonable. Targets and weaponry for particular terrorists organizations tend to vary little. Of course, a volcano can behave differently than in the past, and terrorists can certainly learn new tricks. Although basing estimations of future behavior on past behavior is reasonable in the absence of contrary indicators, there is a danger of missing clues to new behaviors or even, in the case of volcanoes, longer cycles characterized by different behaviors. Fortunately, terrorist groups tend not to last as long as volcanoes. …