A perspective on the levee failures in new orleans from hurricane katrina

The fundamental cause of failure of the levee system in New Orleans following Hurricane Katrina was poor decision making. The design hurricane was not updated over time as new information became available. The inevitable settlement of levees founded on compressible soil was not taken into account. Benchmarks used to establish elevations settled over time, but adjustments were not made. Many sections of levee were built of fine sand and silt materials that were not capable of withstanding erosion from overtopping. Unconservative design assumptions contributed to failure of levees that were not overtopped. Warning signs of imminent failure from a full-scale I-Wall test did not trigger re-consideration of design parameters. These observations lead to the conclusion that the failure of the New Orleans flood protection system was the result of a failure of judgment and decision-making on the part of engineers and the authorizing/funding agencies. The New Orleans levees provide an example of the importance of the first canon of ASCE’s code of ethics: “Engineers shall hold paramount the safety, health and welfare of the public.”