Links between dredge spoil dumping and the marine environment

Dredge spoil refers to unconsolidated, randomly mixed sediments composed of rock, soil, or shell materials extracted and deposited during dredging and dumping activities.  Dredge spoils lie unconformably upon natural, undisturbed soil and can form anthropogenic landforms – dredge spoil bank.
Significant amounts of spoil are created by the dredging for navigation, and to create new or enlarge existing channel, port, marina and boat harbour areas. Dredging for engineering purposes, to create trenches for pipes, cables, immersed tube tunnels, to remove material unsuitable for foundations and to remove overburden for aggregate are also contributors for generated dredge spoil. Dredge spoil, although sometimes used for local land reclamation or deposited on land, is most often deposited at sea.
In the past, spoil was frequently dumped in coastal and ocean waters based on the assumption that marine waters had an unlimited capacity to mix and disperse wastes, while paying little attention to the negative impacts …