The Parramatta River catchment is a unique area with a high biodiversity value. The catchment’s natural resources include bushland, rivers & creeks, wetlands, estuaries and cultural heritage. A total of 85 threatened species are found in the Cumberland sub-region, of which the Parramatta River catchment lies within, including:
- 12 Ecologically Endangered Communities
- 32 fauna species
- 31 flora species
Major wetlands include:
- Bicentennial Park Wetlands (nationally significant, JAMBA CAMBA)
- Newington Wetlands (nationally significant, JAMBA CAMBA)
There is also a wide diversity of aquatic species as well as regionally significant plants and animals throughout the catchment.
Water quality in the catchment is greatly impacted by stormwater runoff. In high rainfall events, large volumes of water enters rivers and creeks, transporting sediment, litter, nutrients, toxic chemicals, herbicides, pesticides, oils and grease, animal waste and sewage. The combined effect of this runoff over time is the degradation and pollution of local waterways as well as siltation and sediment contamination in the Parramatta River estuary.
Research into historical drawings and writings indicates that the significant stands of mangroves that now exist along the River were far fewer at English colonisation. The foreshores of the River were often sandy beaches and outcrops of rock, with extensive tidal flats around Homebush Bay. Excessive siltation of the river has enabled mangroves to thrive, often at the expense of more fragile vegetation communities such as salt marsh.