Alligator Bend Marsh
Landfall of Hurricane Katrina in southeast Louisiana destroyed thousands of acres of marsh and other coastal habitats in the Pontchartrain basin. Atkins provided engineering design services for a foreshore rock dike and vegetative plantings along the shoreline of Lake Borgne. Atkins provided analyses of various alterations of the terraces. Work included determining the still water elevation at mean high water and using the USACE Coastal Engineering Manual (CEM) to determine the wave heights and minimum rock dike/revetment and earthen terrace dimensions to provide protection to the existing marsh area; conducting a sensitivity analysis to demonstrate variability of the input parameters used for the rock dike/revetment and earthen terrace design; developing drawings that included a digital terrain model (DTM) to establish the horizontal alignment of the rock dike segments as a foreshore rock dike and rock revetment; and developing the preliminary and final design folder.