Sediment plume

A sediment plume is the cloud of suspended fines released into the water column by dredging, dredged-material disposal, or fill placement, which then settles or disperses with the current. It raises turbidity and can smother benthos and seagrass downdrift, so it is the main environmental control on dredging windows and method. Overflow from a trailing suction hopper dredger and the cutter at a cutter suction dredger are the principal sources. Plume extent is modeled from the source release rate, the coastal-current field, and settling velocity, and is held within consent limits by turbidity monitoring, silt curtains, or no-overflow dredging.