Numerical models are often used to predict the magnitude and behaviour of dredge plumes to help assess and manage any environmental risks. To provide a realistic prediction of plumes resulting from dredging, numerical models require information on the rate at which sediment is suspended by the dredging, along with the characteristics of the suspended sediment. Previous investigations have shown that in the marine environment, fine-grained sediment suspended by natural processes and dredge-related activities are typically present as aggregated particles known as flocs. This article considers the importance of including the process of flocculation in dredge plume models.
The development of a new marine project demands a system approach in which all aspects, including technical, economic, environmental and social, are considered and integrated equally and at an early stage. While insufficient information may be available to make informed decisions, choices need to be made to progress a project, assess impacts and risks, and engage stakeholders. This article explores the case of a new port terminal in Amatique Bay, Guatemala. A method was developed to assess, at an early stage, the potential negative impacts on seagrass habitats from the disposal of dredged material at different locations, while having limited real-time and location-specific information at hand.