A review of the physical impacts of sediment dispersion from aggregate dredging

The disturbance and subsequent dispersion of sediment arising from aggregate dredging results in increases in suspended sediment concentrations and, potentially, settlement of fine sediment or sand onto the bed, which may both cause adverse effects on local ecology. This subject is one area which has seen much research over many years and this paper sets out to synthesise some basic general conclusions for use when assessing the significance of planned operations. The literature detailing the dispersion of fine sediment plumes, and the longer term dispersion of sand released through the dredging process, is scrutinised, and in some cases re-evaluated, and used to identify an evidence-based footprint of potential impact.