In Depth Look: 5: 2012 Coastal Master Plan
Developing Protection & Restoration Solutions
The Lake Pontchartrain Barrier Project The Lake Pontchartrain Barrier project involves building an earthen levee or floodwall along the New Orleans Landbridge with floodgates on the Rigolets and Chef Menteur Passes to prevent storm surge from entering Lake Pontchartrain. A version of the project has been proposed before and was stopped due to environmental concerns. Our analysis indicated that this project holds great promise for reducing risk throughout the North Shore of Lake Pontchartrain and parts of the greater New Orleans area. The project was also one of the most cost effective risk reduction projects analyzed, providing expected annual damage reduction in Year 50 between $2.1 and $10.4 billion, depending on future coastal conditions. However, our analysis also showed that the project increased storm surge flood levels along the Mississippi coast, as well as in New Orleans East and St. Bernard Parish. Our analysis did not calculate the cost of increased flood damages to Mississippi, making us unable to account for those costs when evaluating the effectiveness of this project. Recognizing the importance and potential of this project, we are dedicating dollars in the master plan to expeditiously determine the most effective way to carry out this project while mitigating any environmental or storm surge issues identified. This investigation will take place in concert with the State of Mississippi and our local partners. At the same time, given the acute need for flood protection on the North Shore and other communities adjacent to Lake Pontchartrain, we did not want to rely solely on this project to provide risk reduction. Instead, the master plan includes other structural and nonstructural projects, such as the Slidell Ring Levee, that will be pursued on a parallel path. These other projects can provide near term risk reduction while the Lake Pontchartrain Barrier project is fully examined. By exploring the barrier project while also providing immediate risk reduction projects for the region, we will be able to effectively address the flooding risk of Lake Pontchartrain’s communities.
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Louisiana’s Comprehensive Master Plan for a Sustainable Coast