Shoreline Response to Harbour Developments in Table Bay

In order to assess the effect of future developments to Cape Town harbour on the sedimentary shoreline of Table Bay, a shoreline model is established. This model is founded on an assessment of the sediment budget and dynamics of the bay together with the calculated nearshore refracted wave field. The model is successfully validated against the measured long-term trends of erosion in the region. Since future erosion to the southern Table Bay shoreline is predicted, a beach nourishment solution is explored. In response to concern that a specific proposed extension to Cape Town harbour may affect the already eroded nearby beaches, an analysis of nearshore wave height and angle changes due to the extension is carried out. This analysis is found to be sufficient to conclude that no effect due to the extension will occur on the sedimentary shoreline situated 2 km north at the end of a seawall. However, indications are that effects on surfing waves adjacent to the development may occur.