State of the Catchments 2010: Hawkesbury–Nepean and Sydney Metropolitan Regions - Estuaries and Coastal Lakes
The Hawkesbury-Nepean and Sydney Metropolitan regions have 16 estuaries, or nine per cent of the total number in New South Wales; 284 km2 or 15 per cent of the total estuarine area in New South Wales; and 23,500 km2 or 18 per cent of the total estuary catchment area.
- 1 November 2010
- Department of Environment, Climate Change and Water
Variation in estuary type, entrance condition, catchment characteristics and climate along the
NSW coast produces estuarine ecosystems that are complex, dynamic and variable. As estuaries
slowly infill, and as development further increases sediment and nutrient inputs, excessive levels
of nitrogen or phosphorus in the estuary can cause algal blooms ('eutrophic' conditions) and other
harmful effects that adversely impact ecosystems as well as human usage.
To adequately capture ecosystem complexity, a number of ecological indicators are being used to
report estuary health covering eutrophication, habitat and fish.