HURRICANE KATRINA FLOOD BY JESSICA KANG Formed over
HURRICANE KATRINA FLOOD BY: JESSICA KANG
�Formed over the Bahamas on August 23, 2005 �Crossed southern Florida (category 1) �Turned into category 3 on August 29, 2005 and caused severe damage along the Gulf Coast from central Florida to Texas �The most severe damage occurred in New Orleans, Louisiana Facts
�At least 1, 836 lives were lost, making it one of the deadliest U. S. hurricanes � 705 are still missing �Costliest hurricane: $88. 5 billion More Facts
�New Orleans is located on a delta formed by the Mississippi River �First settled by the French on the natural levee along the Mississippi bank (known today as the French Quarter) �North of the natural levee, the land slopes down into a swamp History
�Around 1900, large pumps were introduced to drain this wetland ◦ Water was pumped up into canals and drained into Lake Pontchartrain �By 1950, houses and buildings made up the city that we know of today History
�Since New Orleans rests on a delta and it is being drained, the city is continuously sinking �This is because there is peat (unstable organic soil) found in the swamp Geologic Setting
◦ “Consolidation due to loss of water, when the peat loses volume in response to the loss of support offered by internal water pressure ◦ Compaction under load, both self-loading and imposed by other sediments or built structures, when the highly porous peat restructures into a denser material ◦ Wastage on exposure to air, when the peat simply oxidises and disappears where loss of water leaves it above the water table. ” Three Processes Behind Ground Subsidence on Peat
�Knowing that the natural levees would not be enough to protect this sinking city, artificial levees were built. �But they weren’t enough to withstand Katrina. . . Artificial Levees
�Caused by under seepage through the levee silt �The silt washed out and formed “cavities” in the levees, which grew larger �Eventually, the levees collapsed How the Levees Failed
�To rebuild or not to rebuild. . . Ethical issues ◦ Rebuild �Continue building higher levees as the city keeps sinking �Is it the right thing to do to rebuild in a hurricane prone area? ◦ Not to Rebuild �Most people want to hear good news ◦ In the short-run it may be good, but in the long-run? �Who is going to be responsible for the victims? ◦ Many victims were thrown out of their trailer that was provided as shelter after the disaster ◦ Government aid has also been cut off Solutions: It’s Complicated!
� � � � Risk Management Solutions Inc. “Hurricane Katrina: Lessons of a Super Cat. ” http: ///www. rms. com. Web. 24 Feb. 2010. Robertson, Ian N. "Lessons from Hurricane Katrina storm surge on bridges and buildings. " Journal of Waterway, Port, Coastal and Ocean Engineering 133. 6 (2007): 463 -483. Geo. Ref. EBSCO. Web. 24 Feb. 2010. Waltham, Tony. "The flooding of New Orleans. " Geology Today 21. 6 (2005): 225 -231. Geo. Ref. EBSCO. Web. 24 Feb. 2010. Hurricane Katrina. http: //en. wikipedia. org/wiki/Hurricane_Katrina http: //farm 1. static. flickr. com/31/43339467_fbed 13883 f. jpg http: //www. nhc. noaa. gov/HAW 2/english/history/katrina_2005_map. gif http: //lh 3104. k 12. sd. us/Event/katrina-new-orleans-flooding 3 -2005. jpg http: //www. nytimes. com/2009/12/29/us/29 trailer. html? _r=1 Works Cited
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