2006/17 + 2022: Nauiyu Nambiyu/Daly River (Northern Territory) – E.coli, Arsenic, Turbidity, Iron, Manganese

Nauiyu Nambiyu (Daly River) – E.coli

18 – 22 August 2006: Nauiyu Nambiyu (Daly River). High levels of total coliforms found throughout the reticulation system and low E. coli count from one reticulation point

14 – 16 February 2007: Nauiyu Nambiyu (Daly River). High level of both total coliforms and E. coli in a sample taken from the Health Clinic.

2006/07: Nauiya Nambiyu (Daly River). E.coli 5 samples above trigger level. 90.7% below trigger level

2013/14: Nauiyu E.coli 1 detection 98% compliance


Thermotolerant coliforms are a sub-group of coliforms that are able to grow at 44.5 ± 0.2°C. E. coli is the most common thermotolerant coliform present in faeces and is regarded as the most specific indicator of recent faecal contamination because generally it is not capable of growth in the environment. In contrast, some other thermotolerant coliforms (including strains of Klebsiella, Citrobacter and Enterobacter) are able to grow in the environment and their presence is not necessarily related to faecal contamination. While tests for thermotolerant coliforms can be simpler than for E. coli, E. coli is considered a superior indicator for detecting faecal contamination…” ADWG

Nauiyu Nambiyu (Northern Territory) – Arsenic

2008/09: Nauiyu Arsenic 0.013mg/L

2009/10: Nauiyu (Daly River) Arsenic 0.0059mg/L

Arsenic: Australian Drinking Water Guideline = 0.01mg/L

Arsenic is bioaccumulative and symptoms may take 10-15 years to develop after expsoure at high levels. Drinking water can be contaminated with inorganic arsenic through wind blown dust, leaching or runoff from soil, rocks and sediment. Groundwater sources such as bores will usually have higher arsenic levels than surface water. In major Australian reticulated water supplies concentrations of arsenic range up to 0.015mg/L, with typical values less than
0.005mg/L. https://www.health.qld.gov.au/ph/documents/ehu/2676.pdf

Nauiyu Nambiyu/Daly River (Northern Territory) – Turbidity

2008/09: Nauiyu Turbidity 5.8NTU

2009/10: Nauiyu (Daly River) Turbidity 20.5NTU

2010/11: Nauiyu (Daly River) Turbidity 13.4NTU

2013/14: Nauiyu Turbidity 8.2NTU

2016/17: Nauiyu Turbidity 6.4NTU

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.

Nauiyu Nambiyu/Daly River (Northern Territory) Iron

2007/08: Nauiyu Iron 0.65mg/L

2008/09 Nauiyu Iron 1.38mg/L

2009/10: Nauiyu (Daly River) Iron 0.75mg/L

2010/11: Nauiyu (Daly River) Iron 0.57mg/L

2013/14: Nauiyu Iron 0.35mg/L

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

Nauiyu Nambiyu/Daly River (Northern Territory) – Manganese

2008/09: Nauiyu Manganese 0.56mg/L

2009/10: Nauiyu (Daly River) Manganese 0.811mg/L

2019/20: Nauiyu (Northern Territory) Manganese 0.6mg/L (95th %)

2020/21: Nauiyu (Northern Territory) Manganese 0.4mg/L (av.)

2021/22: Nauiyu (Northern Territory) Manganese 0.8mg/L (max), 0.3mg/L (av.)

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 plumbing fixtures

Water in Nauiyu comes out brown. Here’s how remote NT residents are coping


In the remote community of Nauiyu, about 225 kilometres south of Darwin, the water comes out brown.

That is mainly because there is a high level of iron in the ground.

There are no proven health risks of drinking the water, but residents in the area say there is only one way they can make it work.