Deep-Draft Vessels in Narrow Waterway: Port of Oakland 50-Foot Deepening Project

A 3-D hydrodynamic numerical model was developed to analyze the pressure fields generated by deep-draft vessels in the Inner and Outer Harbor Channels. The Vessel Generated Pressure Field (VGPF) model simulates pressure field distributions and calculates water surface elevations in the channels during deep-draft vessel passage. The model output (water surface elevations) was used as input for the Multi-Operational Structural Engineering Simulator (MOSES) model. MOSES is a numerical model that simulates stresses in marine structures and analyzes the structural dynamics of mooring lines, time-history of berthing system response to input wave forcing, and provides time-domain stress analysis. MOSES results were used to identify the capacity of the existing berthing systems to withstand the hydrodynamic forces generated by passing vessels, develop modifications to the existing mooring system, or design a new mooring system if the capacity of the existing system is not sufficient to withstand pressure field impacts. Field data were collected in the Inner Harbor Waterway to validate the numerical model. The long-period pressure field waves were compared with numerical modeling results for each event. The validated VGPF model was used to evaluate the pressure field effects at future berths 55–56 and the existing APL Terminal in the Inner Harbor Waterway, and at Berths 35–57 along the Outer Harbor Waterway. The results of the VGPF model were used as input for MOSES model simulations.