Water quality baseline - regular measurements of its water quality since 2010 have placed Curl Curl Lagoon within lowest 5% -20% tier of lagoons in NSW. Published Lagoon Health Report Cards cover period up until 2015/16. Quality of water in Greendale Creek which feeds Lagoon is always observably poor.
Greendale Creek was not included in Council’s most recent (2014/15) Creek Assessment Report that covered 21 creek sites in Warringah LGA: its water quality is not publicly reported and to our knowledge is not being measured.
Causes of Poor Water Quality – toxins leaching into groundwater coming from under former tip areas on Northern and Southern banks of waterway is main cause of water pollution. A second cause are physical and chemical pollutants washed into waterway from stormwater drains coming from streets in catchment. A third source of pollutants is stormwater entering Greendale Creek from the Brookvale Industrial Area under which a section of the Creek flows.
Humans - are well advised to avoid contact with Lagoon water. A permanent sign at the Lagoon mouth carries this advice.
However - the Park and waterway clearly have natural beauty and high visual appeal. Birdlife is abundant and varied. Fish, eels, turtles and monitor lizards (check variety) can be seen from the bridges. Trees, shrubs and bushes are thriving in large sections of the Park. Rushes edge the banks and at most times there will be significant new plantings visible. All these forms of life are surviving in the Lagoon and Creek