Various management plans within the Environmental Management Programme (EMP), as well as specific Ministerial Conditions from the environmental improvement process, address the potential impacts of dredging, which are:
- Changes in wave climate (i.e. wave height and direction) due to the changes in the water depth created by dredging, and any potential effects on coastal structures (eg groynes, jetties), shipping and navigation and the stability of the seabed and shoreline.
- Loss of seagrass due to dredging
- The effects of turbid plumes created by dredging and wash plant activities on the water quality of Owen Anchorage.
Key EMP elements are:
- A Dredging and Environmental Management Plan for Stage 1, which addresses measuring the effects of turbid plumes created by dredging in the Stage 1 area and wash plant activities, including annual measurements of seagrass health.
- A Seagrass Research and Rehabilitation Plan, as outlined on our Research and Rehabilitation page.
- Decommissioning Plans for Short-Term, Medium-Term and Long-Term Stage 1 and Long-Term Stage 2 dredging areas to ensure that dredged areas represent no liability to the State once dredging ceases.
- A Wave Climate Measurement and Modelling Plan that has carried out detailed measurements of wave climate to confirm the effects predicted by a wave climate model of our previous dredging operations and - when confident the model is suitable - predict the effects of long-term dredging.
- A Shoreline Monitoring Plan that monitors beach profiles in Owen Anchorage twice a year, to make sure any unusual patterns of erosion or deposition are detected.
- A Banks and Shoreline Protection and Management Plan that examines the degree of changes in the seabed and shoreline, and describes what must be done if specific 'triggers' are exceeded.
- Ongoing mapping of marine habitats in Owen Anchorage, with aerial photography every year to check the distribution of seagrass meadows and detailed surveys of the seabed every five years.
- A Dredging and Environmental Management Plan for Stage 2, which addresses measuring the effects of turbid plumes created by dredging in the Stage 2 area and wash plant activities, including potential impacts on seagrass health.
All activities carried out in the EMP are reported each year in our environmental compliance report which is submitted to the Department of Environmental and Conservation (DEC) as a condition of the Ministerial approval.