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The ‘Control’ of Nature in New Orleans: The Past, Present, and Future of the Mississippi Delta Catherine Riihimaki and Rheanna Bensel. No one could have predicted this event… Numerous government officials post-Katrina.
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The ‘Control’ of Nature in New Orleans: The Past, Present, and Future of the Mississippi Delta Catherine Riihimaki and Rheanna Bensel
No one could have predicted this event… Numerous government officials post-Katrina It's only a matter of time before South Louisiana takes a direct hit from a major hurricane. Billions have been spent to protect us, but we grow more vulnerable every day. Times-Picayune, June 23-27, 2002 Five-Part Series on flooding hazards in N.O.
LSU, Center for the Study of Public Health Impacts of Hurricanes
“The Army Corps of Engineers says the system will protect the city and suburbs from a Category 3 hurricane that pushes in enough seawater to raise Lake Pontchartrain 11.5 feet above sea level -- high over the head of anyone standing on the other side of a levee.” --Times-Picayune, 2002
Breached Industrial Canal levee, with water flowing OUT of a residential area August 30, 2005
Humans have dramatically changed the distribution of sediment in the Mississippi River system. • Sediment compacts under its weight; exacerbated by dewatering of sediment (present rate of compaction is ~10x natural rate) • In New Orleans…Levees prevent new deposition of sediment; nothing to counteract subsidence change in elevation = new sediment - subsidence
Humans have dramatically changed the distribution of sediment in the Mississippi River system. • Sediment compacts under its weight; exacerbated by dewatering of sediment (present rate of compaction is ~10x natural rate) • In New Orleans…Levees prevent new deposition of sediment; nothing to counteract subsidence • Sediment load of Mississippi drops off continental shelf; coastal erosion is therefore faster change in coastline = new sediment - wave erosion
Fundamental observation (thanks to Arshiya Bose)… Natural disasters are primarily disastrous because of how humans interact with nature We ought to take a second look at it. But you know we build Los Angeles and San Francisco on top of earthquake fissures and they rebuild too. Stubbornness. -- Dennis Hastert
Fundamental question… How do we deal with dynamic natural systems with a static economy?