The coastal region influences many aspects of our lives, including our economy, our quality of life and our safety and security. Many large cities in Australia are located along estuaries and coasts. As a consequence of the growing human population, most coastal areas throughout Australia are now facing threats of over urbanisation, and industrialisation, resulting in significant impacts on the coastal aquatic environments. Additional challenges may also come from more frequent severe flooding resulting to climate changes, which could degrade the environment even further and more rapidly. Sediment accumulation and transport in estuaries and coastal bays is one of major issues, not only impacting on the maintenance of navigation channel but also resulting in ecological problems. For several decades, a large number of investigations of sediment transport have been conducted in Australia, which them mostly addressing conditions of the sediment delivered to the estuary within the dry season. However, a limited number of researches have been done in great detail, focusing on the hydrodynamic and sediment transport in the wet season. In recent years, with the development of computing and satellite technologies, the study on the hydrodynamic and sediment transport has allowed studies to be conducted on large spatial and temporal scales. Additionally, this has meant it is now easier to investigate the event-driven behaviour severe flooding events.