New Orleans 1980s and 1990s, scientists observed that extensive, rapid, and ongoing erosion of the marshlands and swamp surrounding New Orleans, especially that related to the Mississippi River – Gulf Outlet Canal, had the unintended result of leaving the city more vulnerable than before to hurricane-induced catastrophic storm surges. New Orleans was catastrophically affected by what Raymond B. Seed called "the worst engineering disaster in the world since Chernobyl", when the Federal levee system failed during Hurricane Katrina in 2005. By the time the hurricane approached the city at the end of August 2005, most residents had evacuated. As the hurricane passed
Civil engineering and infrastructure repair in New Orleans after Hurricane Katrina New Orleans area was more than 80 percent unwatered. Corps officials estimated the overall unwatering effort, given normal seasonal rainfall, would be completed no later than early October, 2005. Tropical Storm Rita was being closely watched at this point. Additional traffic in the city in the past three days had caused some delay in traveling to work sites and moving emergency repair equipment. By September 21, 2005, the Army Corps of Engineers had begun closing two damaged canals at noon in preparation for storm surges associated with Hurricane Rita. The 17th Street and London Avenue Canals were closed with steel