Improving Australia’s resilience to coastal erosion
Coastal erosion due to storm surge is an ongoing problem for many areas of the Australian coast. More than 80% of Australians live within the coastal zone, with approximately 700,000 residences (or 6%) within 3 kilometres of the coast and in areas less than 5 metres above mean sea level.
The cumulative impact of successive storms (or storm clusters) is of particular concern to Australians because a series of events may not allow time for a beach to fully recover from the initial storm. This occurred in 1974 when a series of storms caused widespread coastal erosion and property damage along Australia’s south-east coast.
A nationally applicable method for assessing coastal erosion impacts
- By demonstrating an understanding of the impact of storm clusters on the beach environment at two coastal-erosion-affected Australian locations (Old Bar, NSW and Adelaide, SA), Geoscience Australia and partners can now apply the methods used during the study at any location nationally where suitable data is available. This decision-making support to better protect valuable Australian coastal assets is invaluable.
- Coastal managers across Australia are now using a toolkit consisting of proven scientific methods and technical guidelines to find site-specific solutions to coastal erosion, particularly in areas where storm clusters are a possible driver of shoreline change. Infrastructure assets found to have a high exposure risk level are now readily identifiable and have included residential buildings, surf clubs, roads, carparks, beach access paths, stairs, sea walls, groynes and sewer outflows. Management strategies have been instigated to prevent future damage to these structures.
- Government and council coastal managers now have access to modelling techniques to show estimates of the shoreline position and sand volumes that may be eroded from the beach during individual storms or a storm cluster, and the subsequent effects of repeated cycles of storm erosion. They can now calculate the volume of sand required to maintain a buffer of sediment to protect their beaches or dunes against large storms. Access to this new information is helping them develop more targeted beach replenishment programs and recovery plans for specific sections of coastline.
- Scientific estimates of beach erosion caused by storm clusters can now be used to inform management strategies for mitigating the hazard into the future.
