Levees in New Orleans

After reading the about Katrina and talking about it in class it led me to wonder even more about the storm. Although we talked about the religious responses and the effects of Katrina, but what I was most interested in was how the levee system failed and how it works.

Levee wall in New Orleans 

A levee is described as being an elongated naturally occurring ridge or it can be artificially constructed wall which regulates water levels. It is usually made of earth and they're often parallel to the course of a river or along low-lying coastlines. The actual word levee dervives from the French and it means "to raise", yet it is used in American English as well. It originated in New Orleans a few years after the city's founding in 1718. The trait come from the levee's ridges being raised higher than both the channel and the surrounding floodplains. 

The main function of the artificial levee is to prevent flooding and to slow the natural course changes in a waterway for there to be reliable shipping lanes. They are mainly found along the sea where dunes are not strong enough or along rivers and lakes for protection. These kinds of levees require substantial engineering and their surface must be protected from erosion. On the land side of the high side of the levees a low terrace of earth is added as another anti-erosion additive. On the river side, erosion from strong waves or currents cause a greater deal of threat to the stability of the levee.