Clearer drinking water

Yass Valley Council is tackling its discoloured water problems after a new trial manganese removal process implemented by Council in May this year proved successful. It is now being permanently installed.

The trial process was developed by a Sydney chemical engineering firm and utilises chlorine and soda ash to remove the manganese and iron from the water before it leaves the water treatment plant.


The plant currently does not remove manganese, the mineral causing the discolouration.


Yass Valley Council Director of Operations, Simon Cassidy says Council has made significant progress on the issue over the last two months.


“Results of the trial show manganese levels in the water have been reduced from as high as 0.4mg/L in the raw water from the Yass Dam, to around 0.15mg/L.


“This has coincided with a large reduction in complaints received from residents which indicates that the removal of manganese has had an impact on water quality being provided to the community.


“Council undertakes a three tiered testing regime to ensure the continued safety and quality of the water supply.  


“This includes daily tests of pH, turbidity, colour, fluoride and chlorine levels at the treatment plant.


Other tests Yass Valley undertakes are weekly and monthly samples which are analysed at the NSW Health laboratory.


“In addition to the current testing regime, aluminium levels of the raw and treated water are now also monitored weekly and will be analysed by an external chemical engineering firm to investigate any effect on water quality.


“Understanding when and where issues exist allows us to undertake targeted testing and also to do additional mains flushing where persistent issues exist.”