Streambank erosion and floodplain deposition are significant contributors to sediment loads impacting the Great Barrier Reef (GBR). Accurate modelling of these processes is essential to inform effective water quality management and investment decisions. Through a series of projects with the Queensland Water Modelling Network (QWMN), Alluvium has worked to improve how these dynamics are represented in Queensland Government’s GBR catchment models.

Our work focused on identifying key issues with existing streambank modelling approaches and developing a practical framework to support modellers in making more informed, consistent, and evidence-based decisions. This included evaluating erosion processes, data gaps, model assumptions, and parameterisation techniques.

The outcomes of these projects have led to a suite of targeted recommendations aimed at improving the representation of streambank erosion and floodplain deposition. These enhancements will lead to more accurate sediment budgets, helping to better prioritise and target water quality improvement efforts across GBR catchments.