System Simulation of Tidal Hydrodynamic Phenomena in Galveston Bay, Texas

An alternative method, capable of analyzing changes at individual points in an estuary system, as opposed to the global solutions generated by the numerical model, was developed. A system response approach using input/output relationships via nonlinear frequency domain analysis of Fourier Transform from a numerical model to describe the dynamic behavior of tidal hydrodynamic phenomena was used to play this role. Under this design, the system response functions from a verified numerical model for a particular location can be used to simulate the resulting output function, such as change in salinity, when input forcing functions, such as tidal variation and freshwater inflow, change. This approach was applied to address the salinity response due to freshwater inflow changes for 16 selected locations in Galveston Bay, TX. The system model base was constructed by selecting node points from 3-D numerical hydrodynamic model results. The annual numerical simulation of both base geometry (12-m-deep channel) and project conditions (l3.7-m-deep channel) for 1990 medium-flow conditions was used to construct the system response function. Three major tributaries (Trinity River, San Jacinto River, and Buffalo bayou) were considered as primary freshwater inflow sources for conducting these simulations. (MM)