Recovery will take so long, he said, that some workers could spend their entire career working on Katrina. "This is the most significant natural disaster to hit the United States," Lokey said. ..They will eventually end up in the Superdome, where he estimated 15,000 to 20,000 people already have taken refuge and where rising water is threatening the generators. Among the evacuees are 5,000 inmates from New Orleans and suburbs that need to be moved. Officials were trying to figure out how. ...Blanco asked residents to spend Wednesday in prayer. "That would be the best thing to calm our spirits and thank our Lord that we are survivors," she said. "Slowly, gradually, we will recover; we will survive; we will rebuild."