The oceanography of the Sydney region

An understanding of the oceanographic processes affecting effluent plume behaviour formed an important basis for the broad range of activities which were carried out as part of the Sydney Deepwater Outfalls Environmental Monitoring Programme. The main processes responsible for coastal circulation in the Sydney region include the East Australia Current, coastal trapped waves, winds, internal waves and outflows from major estuaries. As each of these processes is dynamically distinct, they occur on differing time and space scales, and the net current strength at any location can vary as differing processes wax and wane in their relative or absolute strength. Each of these processes and their effects on the transport and dispersion of sewage effluent discharged from the Sydney Deepwater Outfalls are briefly described.