Canal Estate Siltation Modelling: A Case Study; Newport Waterways, Redcliffe, Qld, Australia

Newport Waterways is a canal estate on the northern shore of Redcliffe Peninsula with a tidal connection to Deception Bay. Since development commenced in the 1970s, Newport has required maintenance dredging. The initial waterway system was small, with most dredging done by cutter suction dredge in the entrance channel. The current expanded waterway system has a much larger tidal prism, which has led to a major increase in waterway siltation. In the future the waterway will nearly double in size. The causes, patterns and volumes of siltation were assessed for maintenance dredging costing purposes. Siltation was simulated using Delft PART, a Lagrangian particle-tracking model with 400,000 particles. The particles are advected by the mean flow, with a superimposed random displacement in any direction within a specified maximum radius during each time step. Three populations of particles were modelled simultaneously, corresponding to unflocculated clay, flocculated clay and sand. The Delft3D particle tracking model was found to be an accurate simulator of tine sediment siltation problems.