Exploring the Factors which Influence Large Vessel-Generated Waves in a Tidal River*

Large shipping vessels generate highly energetic wake that can contribute significance amounts of energy to the hydrodynamics of a river. A hydrodynamic characterization in the Savannah River, Georgia, indicates that shipping channel traffic between the open ocean and the Port of Savannah is a likely contributor to erosion threatening environmental and cultural resources along the channel. To better understand the mechanisms underlying the erosion, a field study has been conducted to collect water level and velocity data in the channel; approximately 350 wake events are well-captured in this data set. These data are used to characterize persistent patterns in the energy flux and characteristics of ship wake near the shore. The measured wake events are paired with relevant ship data, including ship velocity, length, heading, and draft at the time of wake measurement; they are also paired with numerical model data of the region such that the impacts of tidal current in the shipping channel can be examined. The pairing of ship characteristics, river conditions, and measured wake data provide insight into the factors affecting the total energy and characteristics of large vessel-generated waves.