Feasibility of Beneficial Reuse of Sediment for Mangrove Rehabilitation in Paramaribo, Suriname

Abstract

In response to the escalating coastal erosion at the Weg naar Zee region in Suriname, this study explores the beneficial reuse of dredged sediment from the Suriname River. The integral question is, ”What is the feasibility of the beneficial reuse of dredged sediment through sediment nourishment to rehabilitate the growth of mangrove forest on the Weg naar Zee, Suriname coast?” To address this, literature research provides a basis for understanding imperative areas related to mud coast dynamics, sediment dynamics, mangroves, and the Suriname coastal system. This culminates in a system analysis and develops into a conceptual model of the Suriname River Estuary’s dynamics. Further development of a hydrodynamic numerical Delft 3D model of the Suriname River Estuary system ensues. This analysis forms the foundation for further assessment of potential sediment input locations throughout the estuary. Simulations are utilized to verify the sediment transport mechanisms, primarily focusing on two transport types: initial transport through the water column as suspended particulate matter (SPM), and migration over the bed influenced by wave forcing. These simulations offer valuable data on the impact of timing and placement of sediment input on the transport and deposition process. Employing recent survey data of the Weg naar Zee shoreline’s foreshore, a schematisation was established to ascertain the total infill volume necessary for a convex-up profile favourable for mangrove rehabilitation conditions. The results demonstrate the feasibility of achieving this profile by strategically inputting sediment, hence, capitalising on both transport types in the estuary. The study concludes by reiterating that the strategic placement of sediment nourishments can be a viable means of restoring the Weg naar Zee coastline. Finally, possible subsequent studies to address the existing uncertainties and streamline the implementation strategy are discussed.