New Orleans has only gradually resurrected itself after the city drowned five years ago this week following Hurricane Katrina. That process echoes an unpleasantly familiar drama that has played out countless times around the world during human history.

Building on the coasts and near the fertile floodplains of a river has allowed settlements access to water for trade and agriculture since the earliest days of Egypt and Mesopotamia, according to Greg Aldrete, a historian at the University of Wisconsin in Green Bay. That choice has often come back to haunt people when the floodwaters rose.

"That tension has existed since the very dawn of civilization," Aldrete told LiveScience. "People tend to build cities in floodplains." [Graphic:What Happened in New Orleans]