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Levee Construction Around New Orleans Enters a Period of Uncertainty
The Army Corps of Engineers has embarked on a new study in southern Louisiana that could eventually lead to more levee design and construction alternatives for municipalities in the region. The action raises questions about the most cost-effective types of levees and protection for coastal communities threatened by flooding from volatile weather and nearby bodies of water.
Local governments in the area saw costs rise dramatically when, in response to Hurricane Katrina, the corps developed new regulations mandating that levees protect threatened communities from 100-year storms. These are storms that have a one percent chance of occurring in a given year. If it is successful, the new corps study, formally titled the "Risk Based Criteria Optimization Study," may give communities the option to choose lesser, less expensive levels of protection. A wider array of less-protective levee options would potentially save the governments significant amounts of money and lessen a hefty financial burden that stems from the current requirement that state and local government pay 35 percent of the cost of levee construction.
Many academics and experts are concerned that relaxed flood protection standards and the acceptance of a higher flood risk would be a step in the wrong direction for threatened communities. The proposal has its fair share of critics, including those who believe that it places too much emphasis on the overtopping of levees by storm surge as the principal component of levee failure:
"Ray Seed, a civil engineering professor at the University of California at Berkeley, said the pilot study plan is flawed because it may not adequately consider some of the causes of levee failures in New Orleans, such as floodwaters seeping underneath earthen levees, causing them to collapse or move."