Warragul (Victoria) Manganese
19/3/25: Warragul (Victoria) Manganese 0.61ug/L
“During March 2025, an elevated manganese result was detected at the water entry point for the Warragul system. A result of 0.61 mg/L was detected for a sample collected from the instrumentation wet rack the outlet of the chlorine
contact tank on 19 March 2025. The Guidelines limit for Manganese is 0.1 mg/L for aesthetic considerations and 0.5 mg/L for health-based considerations. The cause of the high manganese result was attributed to an increase in water flow through the sample manifold at the time of
sampling which scoured off and resuspending manganese that had accumulated inside the pipework over time.
Subsequent water samples collected have shown the manganese concentration to be well below both the aesthetic and health-based guidelines. Due to the health based drinking water concentration being exceeded, a Section 18 Notification was submitted to the Department
of Health.” Gippsland Water Annual Drinking Water Quality Report 2024/25
Based on aesthetic considerations, the concentration of manganese in drinking water should not exceed 0.05 mg/L, measured at the customer’s tap. Water authorities are encouraged to keep manganese concentrations as low as possible, preferably below 0.02 mg/L at the treatment plant…
Reviews by the World Health Organization (WHO) and Health Canada found that several human epidemiological studies suggest an association between exposure to manganese in drinking water and neurological effects (e.g. intellectual impairment and poorer neurobehavioural function, including memory, attention, motor function and hyperactivity). Although these epidemiological studies could not establish the level at which oral manganese intake can lead to neurotoxic effects, collectively they provide support that neurotoxicity is a critical effect in humans (WHO 2021; WHO 2022; Health Canada 2019).
Infants, especially newborns, are unable to regulate the levels of manganese in their bodies due to greater gastrointestinal absorption and immaturity of their homeostatic control of bile excretion (i.e. they excrete less manganese) and are more susceptible than other age groups to the neurotoxic effects of excess manganese (WHO 2021; WHO 2022; Health Canada 2019).
Bottle-fed infants may also be at risk of higher manganese exposure due to infant formula which can be fortified with manganese, along with drinking water used to reconstitute the formula which can have elevated manganese levels compared to bottled water (WHO 2021; WHO 2022; Health Canada 2019). ADWG
Warragul (Victoria) – Mercury
March 2012 – Warragul (Victoria) – Mercury 0.0012mg/L
All results below ADWG health guideline values with exception of mercury in Warragul WTP filtered water inlet to reservoir in March 2012 where a result of 0.0012mg/L was reported.No cause was identified for result All subsequent reticulation monitoring was compliant.
Mercury: Australian Drinking Water Guideline 0.001mg/L
Mercury, if it enters the ecosystem can transform into the more toxic methylmercury where it can bioaccumulate. Methylmercury is highly toxic to human embryos, fetuses, infants and children. Mercury has numerous sources including old gold mines, where mercury was used in gold recovery process. It has been estimated that 950 tonnes of
mercury was deposited into Victorian soil, rivers and streams during the various gold rushes.
https://ntn.org.au/wp-content/uploads/2010/05/mercury_brief20101.pdf
Warragul (Victoria) – Iron
2020/21: Warragul (Victoria) – Iron 0.48mg/L (max), 0.02mg/L (average)
2024/25: Warragul (Victoria) – Iron 1.7mg/L (max), 0.037mg/L (average)
Based on aesthetic considerations (precipitation of iron from solution and taste),
the concentration of iron in drinking water should not exceed 0.3 mg/L.
No health-based guideline value has been set for iron.
Iron has a taste threshold of about 0.3 mg/L in water, and becomes objectionable above 3 mg/L. High iron concentrations give water an undesirable rust-brown appearance and can cause staining of laundry and plumbing fittings, fouling of ion-exchange softeners, and blockages in irrigation systems. Growths of iron bacteria, which concentrate iron, may cause taste and odour problems and lead to pipe restrictions, blockages and corrosion. ADWG 2011