Modeling of Oxygen Injection Experiment in Savannah Harbor

A technology that is being considered for improving the dissolved oxygen regime and mitigating impacts due to Savannah Harbor navigation channel deepening is oxygen injection. The injection is exercised by a Speece cone, which pumps water out of the river, supersaturates under pressure, and discharges back into the river to elevate the dissolved oxygen (D.O.). During August 2007, a demonstration project was developed by the Georgia Ports Authority (GPA) to determine if the technology is a viable mitigation option. Tetra Tech, Inc. performed the mathematical modeling as a tool to estimate the effectiveness of the injection experiment. The technical approach uses simulation results of 1) the near-field model (Visual PLUMES), which allows evaluating the size of a mixing zone for the oxygen supersaturated water jet; 2) the far-field model (combination of EFDC and WASP), which allows simulating D.O. dynamics in the harbor; 3) the post processing tool (WAMS), which produces statistics, deltas, visualizations, and other metrics for evaluation of the harbor responses on oxygen injection and other water management measures.