Mathematical simulation of the suspended solids diffusion during dredging operations on the continental shelf off the coast of Lazio (Central Tyrrhenian Sea, Italy)

Artificial nourishment is a preferred strategy to remedy coastal erosion along a sandy coast. To conduct a pilot study on the environmental impact of the use of submerged sandy deposits to artificially nourish beaches, oceanographic and sedimentological studies have been performed in potential dredging sites. The aim was to define the concentrations and characteristics of the suspended solids and the physical and dynamic characteristics of the water masses on the continental shelf (20-100 m) off the coast of Lazio (Italy) to evaluate the possibility of the diffusion and the negative impact of the suspended solids during dredging. The water masses characteristics measured enabled us to develop a predictive model for the suspended solids diffusion that was then applied to the potential sites. In evaluating the possibility of dredging, an application model is useful for determining the behaviour of the different granulometric classes in the dredged sediments and predicting the potential impact of resuspended sediments on the coastal habitat.