DEFINING AN UNUSUAL LITTORAL REGIME TO OPTIMIZE DREDGING AT EAST LONDON

Abstract

Maintenance dredging at the Port of East London is a major annual expense. The aims of this investigation were to obtain relevant information on the sedimentary processes and to apply this information to reduce or optimize various facets of the required maintenance dredging. Information gleaned on various components of the sediment transport regime led to a holistic understanding of the sediment budget for the littoral sub cell at the port. The sedimentary regime is very interesting with a complex pattern of sediment movement around the harbour. In turn, this information could be applied practically in terms of: more efficient sandtraps, a new dump-site closer to the port, a spur which successfully protected the dolos armour units, and proposed extensions to the breakwater which potentially could significantly reduce maintenance dredging. Most of these applications have already led to significant savings on maintenance dredging costs for the port .