Tuggerah Lakes is one of many ICOLS in New South Wales; estuarine systems which alternately have open or closed access to the sea. Many of these are managed to keep the entrance open. A number of different examples of ICOLS was presented. These estuaries are typically very shallow, with poor tidal flushing and dominated by soft sediments, but are also heavily used for fishing, recreation and increasing urbanization. This combination of environmental conditions and human usage has led to varying environmental problems in ICOLS and conflict with stakeholders who perceive different use of these habitats.
The particular environmental issues discussed in this talk, with respect to current problems (perceived or real), management and the proposed permanent opening of the entrance using seawalls included (i) problems with macro-algae blooms and decomposition of vegetation along the shoreline, (ii) potential loss of valuable intertidal habitat, such as saltmarshes, (iii) spread of mangroves, (iv) potential changes to biological processes within seagrass and their flow-on to other components of the environment. Finally, the seawall as a habitat in its own right was described, with respect to species that might settle and live on the wall and species that might accumulate around the wall in the open water.
