In response to hurricane Katrina, the US Army Corps of Engineers decided to increase the frontal protection on four pump stations in the greater New Orleans area. Two of the pump stations (Bonnabel and Duncan) required the construction of wave breaks in Lake Pontchartrain as well as additional frontal protection in the form a T-walls. ALDEN provided wave break design assistance and analysis for using Computational Fluid Dynamics (CFD) tools to evaluate wave break performance. Hydraulic performance of the discharge flow with wave breaks and extended discharge due to the T-wall installation was confirmed with physical hydraulic models.
3-D CFD was used to evaluate the effectiveness of several different wave break designs for reducing the height of the wave impacting the front of the pump station. The wave spectrum used at the model boundaries was derived from the ADCIRC model. Model results were used to improve the wave break design with the objective of minimizing the structure length and maximizing wave height reduction. The models were also used to evaluate the potential impacts of the wave breaks on the erosion and deposition of sediment in the pump discharge canal. Modifications derived in the CFD models were evaluated in two 1:30 scale physical models for final design verification.