You go down to the west bank FEMA office, you find out they're predicting 27 feet of water in New Orleans, in New Orleans, where a million people live, 27 feet of water in a category four storm...
W. J. TAUZIN -- MARCH 21, 1996 U.S. House of Representatives, Subcommittee on Water Resources and Environment, Committee on Transportation and Infrastructure

New Orleans was founded in 1718 by the French under the direction of Jean-Baptiste Le Moyne de Bienville. The site was selected because it was a rare bit of natural high ground along the flood-prone banks of the lower Mississippi. Until the early 20th century, construction was largely limited to the ground along old natural river levees and bayous, giving the 19th century city the shape of a crescent. In the 1910s engineer and inventor A. Baldwin Wood enacted his ambitious plan to drain the swampland in the central part of the city which was bellow sea level. Some pumps designed by Wood and used to drain the original swampland were still in use in 2005. Ever since New Orleans was drained, all rain water has had to be pumped up to the canals which empty into Lake Pontchartrain. As groundwater has been pumped from underneith the city, the city has sunk, increasing the danger of flooding.

The devastation after Katrina hit was predictable. "40% of Louisiana, is classified as coastal zone; 90% of this zone being near or below sea level; and 70% of Louisiana’s population residing in the coastal zone. This includes New Orleans with its 500,000 population at risk, and estimated potential insured losses exceeding $25 billion". The levees surrounding the city of New Orleans were designed to withstand a Category 3 storm but it was known that the city risked major flooding if anything larger hit. In 1965, a Category 3 hurricane named Betsy made landfall within 20 miles of New Orleans, killing 75 people. Since then New Orleans has worked to strengthen its levee system but "computer models have shown that a Category 3 storm moving at 5 to 7 mph would leave much of New Orleans under eight feet of water". "All of a sudden you'll start seeing flowing water. It'll look like a weir, water just pouring over the top," an engineer who was studying the impact arned. The water will flood the lakefront, filling up low-lying areas first, and continue its march south toward the river. There would be no stopping or slowing it; pumping systems would be overwhelmed and submerged in a matter of hours. "Another scenario is that some part of the levee would fail...It's not something that's expected. But erosion occurs, and as levees broke, the break will get wider and wider. The water will flow through the city and stop only when it reaches the next higher thing. The most continuous barrier is the south levee, along the river. That's 25 feet high, so you'll see the water pile up on the river levee."

It was also known that evacuation of the city would be difficult. When Hurricane George almost hit the city in 1998, Charlie Ireland, assistant director of emergency management stated "New Orleans is a real problem. It takes a long time to evacuate, plus it's surrounded by water and levees." The director of the American National Hurricane Centre warned that New Orleans, which is protected by levees from the water which surrounds it, was especially difficult to evacuate because it is connected to the rest of the country by only two main roads.

Massive numbers of deaths in the US following Hurricanes are not new, "The greatest natural disaster in U.S. history occurred on September 8, 1900, when a hurricane struck Galveston, Texas, killing more than 6,000 people." Dealing with the flooding of New Orleans was third on a FEMA list of worst dangers facing the US and when Hurricane Lili hit Louisiana in 2002, the Mississippi Valley Divisiona activated an operation plan that for the first time, transferred responsibility for executing FEMA missions in Louisiana from the New Orleans District to the Memphis District in case the devastation was bad enough that the New Orleans district would be unable to respond.

The Big One | New Orleans preparing for hurricanes | The Lowdown of Levees | OH NO: Mr. Bill Knew, So Why Didn't Washington? | In 2004, A Category 5 Hurricane Hit Cuba, But Due To Good Planning Nobody Died