<P> Amtrak, America's rail passenger carrier, announced that the southbound City of New Orleans passenger trains from Chicago, Illinois, from August 29 through September 3, would terminate in Memphis, Tennessee, rather than their usual destination of New Orleans . The corresponding northbound trains would also originate in Memphis . The southbound Crescent from New York City, for the same period, terminated in Atlanta, Georgia, with the corresponding northbound trains originating in Atlanta as well . Amtrak's westbound Sunset Limited originated in San Antonio, Texas, rather than its normal origin point of Orlando, Florida . Amtrak announced that no alternate transportation options would be made available into or out of the affected area . </P> <P> The Waterford nuclear power plant was also shut down on Sunday, August 28, before Katrina's arrival . </P> <P> By August 26, the possibility of unprecedented cataclysm was already being considered . Some computer models were putting the city of New Orleans right in the center of their track probabilities, and the chances of a direct hit were forecast at 17% (with strike probability rising to 29% by August 28). This scenario was considered a potential catastrophe because 80% of the New Orleans metropolitan area is below sea level along Lake Pontchartrain . Since the storm surge produced by the hurricane's right - front quadrant (containing the strongest winds) was more than 20 ft (6 m) near Biloxi, emergency management officials in New Orleans feared that the storm surge could go over the tops of levees protecting the city, causing major flooding . This risk of devastation had been known for some time; previous studies by FEMA and the Army Corps of Engineers had warned that a direct hurricane strike on New Orleans could lead to massive flooding, which would lead to thousands of drowning deaths, as well as many more suffering from disease and dehydration, as the flood waters slowly receded from the city . </P> <P> At a news conference 10: 00 AM on August 28, shortly after Katrina was upgraded to a Category 5 storm, New Orleans mayor Ray Nagin ordered the first ever mandatory evacuation of the city, calling Katrina, "a storm that most of us have long feared". To speed up the evacuations, authorities used contraflow lane reversal on Interstate 10 leading west of New Orleans, as well as on Interstate 55 and 59 leading north from the city . The city government also established a "refuge of last resort" for citizens who could not leave the city, at the massive Louisiana Superdome, which housed approximately 26,000 people with food and water for two days as the storm came ashore . The Louisiana National Guard delivered three truckloads of water and seven truckloads of MRE's to the Superdome, enough to supply 15,000 people for three days . </P>

How much notice did new orleans have before katrina
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