SCIPP discusses improvements since Hurricane Katrina's impact

Aug 31 2010

Southern Climate Impacts Planning Program discusses improvements since Hurricane Katrina's impact

Five years ago, New Orleans was hit by one of the worst natural disasters in U.S. history. Three years later - almost to the day - the city survived another major hurricane with barely a scratch. What happened to make the outcomes of Hurricane Gustav so much different from Katrina? LSU's Climate Center, part of the Southern Climate Impacts Planning Program, or SCIPP, which partners LSU with the University of Oklahoma, released "Beyond Katrina: Lessons Learned," to evaluate the progress New Orleans, the state of Louisiana and the Gulf Coast region have made since Katrina's devastating impact in 2005. According to these scientists, the differences in impact were the culmination of lessons learned, not only from Katrina, but from a series of events dating back a decade.

The information below has been condensed from a presentation given at the 2009

American Meteorological Society Conference by LSU's Barry Keim; Mark Shafer of the Oklahoma Climatological Survey; and University of Kentucky's Gina Eosco. To view the document in its entirety, visit http://www.southernclimate.org/documents/AMS_2009.pdf.

According to SCIPP, one has to understand planning that came out of previous storms and the human response to them before understanding the current strategies. Hurricane Georges threatened New Orleans in 1998, before veering sharply to the right and making landfall in Biloxi, Miss. Evacuation was uncoordinated and chaotic, demonstrating how ill-prepared the region was to handle a mass evacuation. Each area had its own separate response plan. The timing was not coordinated, resulting in clogged roadways and difficulty getting out of harm's way.

The Hurricane Pam exercise in 2004 revealed further weaknesses in evacuation strategies. Assuming a 65 percent evacuation rate for the metropolitan area, it left 600,000 people behind to ride out the storm. The scenario forced planners to identify where they would obtain needed supplies; they could just not assume materials would show up. But despite its thoroughness, the exercise did not address longer-term issues, including temporary housing, relocation of displaced people and pets, post-event security, re-entry to the city by returning residents and FEMA's promised stockpiles of provisions - all issues that would resurface with Katrina.

Just months after the Hurricane Pam exercise, Hurricane Ivan seemed to have New Orleans in its sights before, like Georges, it made a sharp right turn before landfall and weakened. Unlike Georges, however, Louisiana officials had vastly improved coordination of its state and parish evacuation plans. Contraflow, turning the inbound lanes of major highways to outbound, was implemented, moving people swiftly away from the coast. But it also revealed that better coordination was needed with neighboring states, as Mississippi did not implement contraflow, creating bottlenecks at state borders.

While Katrina is well-known for being among the worst U.S. disasters, there is an often untold story of the success of the evacuation. Learning from Hurricanes Georges, Pam and Ivan, more than 1 million people from the New Orleans metropolitan area were evacuated within 36 hours, representing more than 80 percent of the region's population and far exceeding the projections from the Hurricane Pam exercise. Coordination of evacuations between neighboring states improved traffic flow, even though more people across a much larger area of coastline evacuated.

The failure of Katrina lay in the unresolved issues from Hurricane Pam. Those who were not able to evacuate by their own means relied on services that were unavailable. Rental cars, buses and ambulances were in short supply and many public transportation systems were shut down well in advance of the storm. Damage from the storm severed transportation arteries going into and out of New Orleans, leaving hundreds of thousands stranded. Local resources were in short supply and federal materials failed to materialize as promised.

Hurricane Gustav proved to be a different story. Officials began taking action while Gustav was still a tropical storm far out in the Caribbean, seven days before landfall. Assisted evacuations began four days ahead of projected landfall and contracts were exercised to obtain as many as 700 buses - all of this while Gustav was still a tropical storm.

Three days before landfall, Mayor Ray Nagin issued a mandatory evacuation for New Orleans. By the time Gustav arrived, nearly 2 million residents along the Gulf Coast had left, including 95 percent of the population of New Orleans, making it the largest evacuation of the U.S. coastline in history.

SCIPP researchers contend that Katrina was just one milestone along the way toward making New Orleans safer. In fact, New Orleans, the state of Louisiana and the Gulf Coast region had already learned a great deal prior to Katrina. Those lessons, in addition to the lessons learned from Katrina made for arguably the most efficient and orderly evacuation of a large urban area ever conducted.

While Gustav proved that officials learned from the past, there remain unresolved issues. While hurricane track forecasts have improved tremendously over the past decade, forecasting hurricane intensity at landfall is still a challenge. Related impacts of storm surge are another forecast challenge, making it difficult for officials to precisely target areas where evacuation is needed. What if multiple evacuations are needed in a single year, like in Florida in 2004? Will people be willing to evacuate a second, third or even fourth time?

The SCIPP report states that Hurricane Gustav proved it was possible to evacuate large population areas along the coastlines, including those who are not capable of evacuating by themselves. Coordination between Louisiana, neighboring states and the federal government moved those in need to shelters far away from New Orleans and then returned them within a matter of days. Louisiana officials deserve a great deal of credit for the seriousness with which they took the situation, at the first indication of a threat, keeping them ahead of events. The progression of events highlights the trust officials placed in improved forecasting, the role of planning and the extent of learning from prior experience.

Source: Louisiana State University