[A Wal-Mart in Festus, Missouri, photographed on July 9, 1993.  The Great Mississippi and Missouri Floods of 1993 were the most costly in the history of the United States, causing some $15 billion in damages, and inundating vast swathes of North Dakota, South Dakota, Nebraska, Kansas, Minnesota, Iowa, Missouri, Michigan, Illinois, and Indiana.  In some locations, flood conditions persisted for a record-breaking 200 days.  Because the Ohio Valley was relatively dry that spring and summer, the flooding was confined to the Upper Mississippi.]