2010/11 + 2016/23 – Lilydale (Victoria) – Turbidity, Iron

Lilydale – Victoria – Turbidity

2010/11: Lilydale (Victoria) – Turbidity 5.4 NTU (Maximum detection during year)

2016/17: Lilydale (Victoria) – Turbidity 6.2 NTU (Maximum detection during year)

2020/21: Lilydale (Victoria) – Turbidity 5.6 NTU (Max), 1.95 NTU (95th percentile)

2022/23: Lilydale (Victoria) – Turbidity 5.5 NTU (Max), 1.36 NTU (95th percentile)

Chlorine-resistant pathogen reduction: Where filtration alone is used as the water treatment
process to address identified risks from Cryptosporidium and Giardia, it is essential
that filtration is optimised and consequently the target for the turbidity of water leaving
individual filters should be less than 0.2 NTU, and should not exceed 0.5 NTU at any time
Disinfection: A turbidity of less than 1 NTU is desirable at the time of disinfection with
chlorine unless a higher value can be validated in a specific context.
Aesthetic: Based on aesthetic considerations, the turbidity should not exceed 5 NTU at the
consumer’s tap.

Lilydale (Vic) – Iron

2020/21: Lilydale (Vic) – Iron 0.79mg/L (max), 0.04mg/L (min), 0.11mg/L (mean)

2022/23: Lilydale (Vic) – Iron 0.392mg/L (max), 0.066mg/L (mean)

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