Southeastern Section - 68th Annual Meeting - 2019

Paper No. 3-3
Presentation Time: 8:45 AM


HANEBUTH, Till J.J.1, DURICA, John T1, MEYERS, Ezekiel W1, ZHANG, Wenyan2 and PORZ, Lucas2, (1)Department of Coastal and Marine Systems Science, Coastal Carolina University, 301 Allied Drive, Conway, SC 29528, (2)Institute of Coastal Research, Helmholtz Centre for Materials and Coastal Research, Max-Planck-Strasse 1, Geesthacht, 21502, Germany

Georgetown’s Working Waterfront is a vital place with local businesses, traditional fishery, and daily tourism. The unique historical heritage and beautiful scenery deserve to be preserved and cultivated. Full access from the river side is key to ensure a navigable waterfront, which, however, has a chronic silting issue at its entrance. The silting is a consequence of a short-cut dug by the US Army Corps of Engineers in 1949, which converted the river harbor meander into an artificial oxbow. Since, dredging the harbor loop was always required and its termination in 2006 led to immediate harbor shallowing.

This sediment- and hydro-dynamic study seeks for a lasting, sustainable, and cost-efficient technical solution against the massive mud accumulation. The central question is how parts of the bottom current, which ceased with the short-cut, can be regenerated. It is essential, however, also to estimate in advance which strength is high enough to flush the silts out, which direction the silts will be moved, where local erosion might occur along the infrastructure, and which impact storm surges might have.

We currently monitor water level and turbidity data around the harbor together with sedimentological and geochemical properties of the seabed sediment inside and around the harbor, and also include the limited amount of data sets measured previously. These field data feed a numerical coastal-ocean hydro-dynamic sediment-transport model, which will help to simulate modern water flow conditions and modern sediment transport and settling processes. The ultimate goal is the numerical simulation of various technical scenarios that might help to generate water flow in the harbor loop with the least economic and ecological impacts.

This project is jointly funded by City and County of Georgetown. We thank colleagues from SC DNR, SC Port Authority, SC DOT, US Coast Guard, USACE, USGS, EPA, USC Columbia, the Georgetown Maritime Museum, and the Georgetown Working Waterfront Coalition for their great support.