Development of Inner Harbor Navigation Canal Hurricane Surge Barrier Project Hydrodynamics through Deterministic Methods, Physical Modeling, and Numerical Modeling

The Inner Harbor Navigation (IHNC) Surge Barrier project will provide 1.0% chance exceedance (or 100-year) storm risk reduction to eastern New Orleans from powerful hurricane storm surges and waves from the Gulf of Mexico. Two navigation gates along the 2.7 km surge barrier can be closed to prevent water surging up the IHNC into the heart of the city. This paper discusses the methodology to derive the hydraulic boundary conditions for design, including the deterministic methods and physical and numerical modeling used for verification and investigation of other specific design purposes. Probabilistic synthetic storms were used to provide initial storm surge and wave climate characteristics. Deterministic calculations were then used to shoal waves and calculated wave loads and overtopping. 2-D and 3-D 1:20 Froude scaled physical models were employed to verify hydrodynamic loading and stability, while also allowing investigation of characteristic overtopping and scour. Additionally, depth averaged RMA2 modeling was utilized for investigation of localized affects to navigation through the gates.