tiveness of any hazard insurance program. Some questions address institutional relationships such as the methods by which regulators can monitor insurers’ catastrophe and insolvency risks and intervene to protect policy-holders. Other questions address individual decision processes, such as how insurance premiums can be structured to encourage people to avoid hazard-prone areas where appropriate, to purchase insurance if they do decide to live there, and to implement hazard mitigation practices that reduce the likelihood of losses.

tion analyses conducted four years earlier, the over-response to Hurricane Rita greatly exceeded expectations because only 18 percent of the population of these counties is within officially designated hurricane risk areas. The excessive evacuation rate (327 percent of the projected rate) cannot be attributed solely to over warning because only 25 percent of the households reported receiving a mandatory evacuation order and another 12 percent reported receiving a voluntary evacuation order. Nor was it due only to misperception of risk because only 36 percent thought they were at either high or moderate risk from the hurricane. Thus, further research is needed to determine more clearly why so many households evacuated and if this over response is likely to occur in future hurricanes. In addition, the Hurricane Rita evacuation indicates a need for better methods of hurricane evacuation management. In particular, the evacuation analyses conducted for the state of Texas predicted that traffic queues could form in the hurricane surge zone south of Houston if a hurricane tracking directly west made a late change in direction to the north, as was the case for Hurricane Bret in 1999 and Hurricane Charley in 2004. Such a scenario could cause thousands of deaths if the evacuation were initiated less than 24 hours before landfall. During Hurricane Rita, the evacuation queues formed much earlier and about 20 miles farther inland than predicted in the Texas evacuation analyses because the storm tracked directly toward the Houston-Galveston area. Consequently, local officials initiated evacuations approximately 60 hours before landfall. Even though the late changing track scenario did not occur in Hurricane Rita, it might happen in a future hurricane. The likelihood of a major loss of life in this scenario could be reduced by better highway capacity management techniques such as contra flow. However, this technique is difficult to implement and can only increase capacity by 50-75 percent. Even greater safety can be provided by better evacuation demand management that uses more effective risk communication, improved structural protection works, better land-use practices, and better building construction practices to sharply reduce the number of evacuating vehicles. A significant amount of research will be needed to support the development of feasible hurricane hazard mitigation and emergency response preparedness plans.



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