LOW water levels and warmer water temperatures are behind the recent number of dead fish in Bellambi Lagoon an investigation has found.
NSW Health and Sydney Water has confirmed that the fish kill was not related to sewerage contamination. However, while the water levels and quality are low, and drought conditions persist, Wollongong City Council is advising the community to stay out of the water in the lagoon area.
The investigation by NSW Health and Sydney Water has confirmed no identified sewerage issues at Bellambi Lagoon and East Corrimal Beach. The investigation was instigated by the discovery of a number of dead fish at Bellambi Lagoon, at the end of the lagoon closest to the ocean inlet where water levels are low.
Samples taken by Sydney Water at both locations on December 29 showed some water quality indicators exceeded guidelines for primary contact recreational waterways. However, further investigations confirmed no identified sewerage issues.
While Sydney Water and Wollongong City Council caution signs at Bellambi Lagoon and East Corrimal Beach have now been removed, Council will place further signs around the lagoon to advise the public against entering the water while water levels remain low.
Wollongong City Council’s director of planning and environment Linda Davis said while the most recent water testing has shown that there are no sewage issues, there may still be public health risks associated with the water quality for the foreseeable future while drought conditions persist and there is a risk that a fish kill may reoccur.
“NSW Fisheries has advised that the cause of the fish kill was low dissolved oxygen levels within the waterbody, suffocating the fish,” she said.
“This is likely to have been caused by higher water temperatures, low water levels/flows and the decay of algae around the edges. Similar fish kills are currently being reported along the NSW coast and are often common during hot weather periods.
“They further advised that on 1 January fish were observed behaving normally within the lagoon, indicating that dissolved oxygen levels had likely increased again, allowing fish to breathe.”