Water Quality and Treatment
Expand the sections below to learn more about water quality and water treatment from Dubbo Regional Council for the Local Government Area.
DRINKING WATER QUALITY
Council supplies drinking water to the residents of Dubbo, Eumungerie, Mogriguy, Wellington, Geurie, Mumbil, Brocklehurst, Wongarbon and Ballimore. Drinking water is also sometimes called “potable” water. Non-potable water refers to water that cannot be directly consumed safely.
Further Information on drinking water quality management is contained within Council's Water Supply Services Policy, view this policy at Council's dedicated webpage; A-Z Council Policies.
The generally accepted drinking water quality guidelines for drinking water quality in Australia and New Zealand today are developed and updated by the National Health and Medical Research Council (NHMRC). The Australian Drinking Water Guidelines 2011 also reflect these international guidelines, such as those developed by the World Health Organisation (WHO) and the results of current medical research. Below are the accepted values for various parameters and a value typical of Dubbo’s Water supply:
| Parameters |
ADWG - 2011 |
Typical Dubbo Water Value |
Hardness as CaCO3 |
200 mg/l |
80 mg/l |
pH
|
6.5 – 8.5 |
7.5 – 8.5 |
Taste & Colour
|
Not Necessary |
Acceptable to most people |
| Total Dissolved Solids |
600 mg/l |
250 mg/l
|
| True Colour |
Not Necessary |
<5TCU |
| Turbidity |
<5 NTU |
<1 NTU |
| Thermotolerant Coliforms |
None in 100 ml |
0 |
| Total Coliforms |
# No guideline value set |
# |
| Chlorine (Max) |
5 mg/l |
1.40 mg/l |
| Aluminium |
<0.2 mg/l |
<0.1 mg/l |
| Ammonia as NH3 |
<0.5 mg/l |
0 mg/l |
| Antimony |
<0.003 mg/l |
<0.003 mg/l |
| Arsenic |
<0.01 mg/l |
<0.001 mg/l |
| Barium |
<2.0 mg/l |
<0.009 mg/l |
| Boron |
<4.0 mg/l |
<0.3 mg/l |
| Cadmium |
<0.002 mg/l |
<0.001 mg/l |
| Chloride |
<250 mg/l |
<80 mg/l |
| Chromium (as CR (VI)) |
<0.05 mg/l |
<0.01 mg/l |
| Copper |
<2.0 mg/l |
<0.7 mg/l |
| Cyanide |
<0.08 mg/l |
<0.08 mg/l |
| Fluoride |
<1.5 mg/l |
0.08 to 0.12 mg/l * |
| Iron |
<0.3 mg/l |
<0.1 mg/l |
| Lead |
<0.01 mg/l |
<0.01 mg/l |
| Manganese |
<0.5 mg/l |
<0.03 mg/l |
| Mercury |
<0.001 mg/l |
<0.0001 mg/l |
| Nitrate (as NO3) |
<50 mg/l |
<8 mg/l |
| Nitrite (as NO2) |
<3 mg/l |
0 mg/l |
| Selenium |
<0.01 mg/l |
<0.005 mg/l |
| Sodium |
<180 mg/l |
<60 mg/l |
| Sulphate |
<250 mg/l |
<30 mg/l |
| Zinc |
<3 mg/l |
<0.3 mg/l |
| Hydrogen Sulfide |
<0.05 mg/l |
0 mg/l |
| Iodide |
<0.1 mg/l |
<0.1 mg/l |
| Molybodenum |
<0.05 mg/l |
<0.05 mg/l |
| Nickel |
<0.02 mg/l |
0.02 mg/l |
| Silver |
<0.1 mg/l |
<0.1 |
* Due to operational reasons Council is unable to add additional fluoride to the Dubbo water supply service area. The National Health and Medical Research Council supports Australian States and Territories fluoridating their drinking water within the range of 0.6 to 1.1mg of fluoride per litre.
# No guideline value has been set for Total Coliforms
PER- AND POLY- FLUOROALKYL SUBSTANCES (PFAS)
PFAS chemicals or per- and poly- fluoroalkyl substances are synthetic chemicals found in many everyday products. They have been widely used in many industrial and consumer applications as they are effective at resisting heat, stains, grease and water.
The National Health and Medical Research Council (NHRMC) has stated that drinking water supplies that comply with the current Australian Drinking Water Guidelines (ADWG) is safe to drink.
The guideline values show the amount of PFAS in drinking water that a person can consume on a daily basis over a lifetime without any appreciable risk to health.
On Wednesday, 25 June 2025, the NHMRC released updated health-based guidelines which outline new, lower recommended values of PFAS in drinking water. Read more at their webpage; PFAS and drinking water - information and updates
Water providers are not legally required to meet the new drinking water guidelines until the finalised guideline values are published in the ADWG and adopted by each state and territory.
It is expected that it will take time and resources to implement the new PFAS guideline values in Australia.
For further information about PFAS please refer to the fact sheet from the Water Services Association of Australia (WSAA); Per- and Poly-Fluoroalkyl Substances (PFAS) Fact Sheet
Council undertakes a regular sampling program of source and treated water for PFAS in accordance with the ADWG and NSW Health standards.
The most recent sample results conducted by a National Association of Testing Authorities (NATA) accredited laboratory are presented in the below table.
Characteristic
|
Current ADWG value
|
NHRMC Revised Value
|
Unit |
Dubbo Regional Council Water Supply Systems - Sample Results (µg/L) |
| Dubbo John Gilbert Water Treatment Plant - date sample taken 18/06/2025 |
Wellington Water Treatment Plant - date sample taken 11/06/2025 |
Geurie Water Treatment Plant - date sample taken 11/06/2025 |
Mumbil Water Treatment Plant - date sample taken 11/06/2025 |
| Perfluorooctanoic acid (PFOA) |
0.560 |
0.2 |
µg/L
|
<0.002 |
<0.002 |
<0.002 |
<0.002 |
Perfluorooctane sulfonic acid (PFOS)
|
Sum of PFOS and PFHxS = 0.07 |
0.008 |
µg/L |
<0.002 |
<0.002
|
<0.002 |
<0.002 |
Perfluorohexane sulfonic acid (PFHxS)
|
0.03 |
µg/L |
<0.002 |
<0.002 |
<0.002 |
<0.002 |
Perfluorobutane sulfonic acid (PFBS)
|
No current guidelines value |
1 |
µg/L |
<0.002 |
<0.002 |
<0.002 |
<0.002 |
WATER MAINS CLEANING
Council periodically undertakes a system wide water mains flushing program to protect the quality of the drinking water supply to residents, and to minimise the risk of water main breaks. This program is part of Council’s ongoing maintenance of the water reticulation network.
Council frequently tests water quality throughout the system to check that the water remains safe to drink and meets Australian Drinking Water Guidelines.
FLUORIDATION OF WATER SUPPLY
Water fluoridation is the process of adjusting the amount of fluoride in drinking water to an optimal level to help reduce tooth decay. National Health and Medical Research Council (NHMRC) supports Australian states and territories fluoridating their drinking water supplies within the range of 0.6 to 1.1 milligrams of fluoride per litre (mg/L) (3).
Water utilities such as Dubbo Regional Council add fluoride to drinking water to reduce tooth decay in children and adults. Good dental health is extremely important for people's overall health and wellbeing. Adding fluoride to drinking water keeps teeth healthy and reduces costs for everyone in our community. This is especially important for people who might not have regular access to dental services.
Most people get fluoride every day when they brush their teeth or drink tap water. Fluoride is a natural mineral found in soil, rocks, and water, but the water in the rivers and dams that provide our drinking water usually does not have enough fluoride to prevent tooth decay.
Fluoride helps to repair teeth with early signs of tooth decay before cavities form. It also helps children’s teeth be more resistant to tooth decay as they are forming – protecting them right from the start.
Fluoride is currently not introduced in the drinking water for the Dubbo Local Government Area due to fluoridation equipment failure. Construction and installation of a new fluoride dosing system is underway for Dubbo’s John Gilbert Water Treatment Plant and the Wellington Water Treatment Plant to allow water fluoridation to be reinstated.
COUNCIL RESPONSIBILITIES
For information on the range of legislative requirements and responsibilities of Dubbo Regional Council related to water and sewer view our dedicated webpage; Council's Water and Sewer Responsibilities
Last Edited: 21 Jul 2025