Ports are a critical component of Australia’s transport infrastructure and economy. For vessels to safety access port facilities without risk of grounding, many ports require regular maintenance dredging programs to maintain shipping infrastructure to safe navigable depth. Maintenance dredging is conducted in accordance with approved long-term dredging management plans. Under these plans, and in accordance with the NAGD (2009) dredged material that is suitable for unconfined ocean placement is placed offshore in approved relocation areas; in Tropical Queensland these areas are usually within or adjacent to the Great Barrier Reef Marine Park.
The 2019 GBR outlook report recognises the importance the lagoon floor and associated soft sediment communities play in maintaining the ecological health of the GBR. Understanding the resilience of these communities to the regular disturbance of dredged material placement is therefore critical for effective management of Port environments.
Here we present findings from case studies that have assessed benthic communities and sediment compositional characteristics at sites of relevance to designated placement areas. Assessment has been undertaken over varying spatial and temporal scales to inform understanding of drivers of change. Findings will support ongoing improvements of environmental protection measures associated with Port management of maintenance dredging activities.