Casuarina Park, Annandale – Queensland – Manganese
Incident Description: Detection of Manganese (1.1mg/L) at Casaurina Park, Annandale on 17th
February 2016. This was a highly unusual sample. Historically there has never been an issue with elevated Manganese (Mn) in the Townsville drinking water system. There is no Mn in the treated water from Douglas WTP. No other sample taken on the day had elevated Mn. Public health would not have been affected as the tap was a vandal proof tap, not accessible to the public, on a grass verge that is not used by the
Corrective and Preventative Actions: All Manganese data was analysed. Resamples were taken, both at this point and at nearby points. All resamples came back as well below ADWQ Guidelines or not detected. It is unclear what caused the elevated Mn. The sample tap was removed and a more representative sample point is now in use. Elevated Mn has not been
detected anywhere in the Townsville Drinking Water Scheme since.
Manganese: ADWG Guidelines 0.5mg/L. ADWG Aesthetic Guideline 0.1mg/L
Manganese is found in the natural environment. Manganese in drinking water above 0.1mg/L can give water an unpleasant taste and stain plumbling fixtures and laundry.