Water Quality Monitoring

Drinking Water Quality Monitoring

Council provides safe and reliable drinking water to approximately 18,000 people in the Singleton Local Government area every day.  Our drinking water is regularly tested throughout the water supply system and analysed by independent NATA certified laboratories, as governed by the Australian Drinking Water Guidelines (ADWG) 2011.

If a problem with water supply is identified, the NSW Health Department will issue a boil water alert. Council consults with NSW Health to ensure current and emerging issues associated with drinking water quality are identified and assessed.

Drinking Water Management System 

A secure and safe supply of drinking water is fundamental to public health. The NSW Government has endorsed the Australian Drinking Water Guidelines 2011 (published by the National Health and Medical Research Council and the Natural Resource Management Ministerial Council). 

Council’s Drinking Water Quality Management Manual and Supporting Documents has been structured by the 12 elements of the ADWG, as are the NSW Guidelines for Drinking Water Management Systems.  It is made up of the following document hierarchy;

  1. Water Quality Statement; included in the Water Supply Services Policy
  2. Drinking Water Manual
  3. Supporting documents
    Drinking Water System Analysis (separate report)
    Risk Assessment Report (separate report)
    Monitoring Plan (Appendix J - Drinking Water Manual)
    Improvement Plan (Appendix I - Drinking Water Manual)
  4. Procedures in relation to the following topics:
    Operation and maintenance (section 4 - Drinking Water Manual)
    Emergency response (section 6 - Drinking Water Manual)
    Quality assurance (Monitoring Plan and section 7 - Drinking Water manual)
    Critical control point (Appendix D - Drinking Water Manual and Monitoring Plan) 


Common Quality Issues

Dirty Water

What is dirty water

'Dirty' water is a change in the appearance or the colour of your water - usually to a brown or yellow. Sudden increase in the rate or direction of water flow in the mains can stir up sediment.  This becomes suspended in the water making it appear dirty. Discolouration is caused by trace materials in the water, such as iron or manganese.

When these materials enter the water supply system they are in extremely low levels; generally, dirty water is harmless and the water is safe to use and is not hazardous to health, although it may appear unpleasant.

Residents living in areas furthest away from the nearest reservoir, or at the end of a street, may experience discolouration more frequently than others. This is because the water has further to travel and this allows heavier particles to settle out of the water and become visible. Weekenders or untenanted houses in any area may also experience discolouration when first turning on a tap after a period of time without using water at the home. 

Dirty water can be the result of planned or unplanned scouring and/or galvanised pipes in older homes.

From Scouring

Dirty water most often occurs when flushing of the mains, known as scouring occurs.  Scouring is the cleaning of the inside of water mains by sending a rapid flow of water through the main under high pressure.  During this process the build-up of sediment will be dislodged.  Some discolouration of the water supply may occur after mains flushing in the immediate area, this will quickly disperse after running a tap for a short period of time.

If you experience dirty, or discoloured water after a scheduled clean, try running the outside tap for 1 to 5 minutes until the water clears.  And avoid doing laundry.

Council will notify residents of any planned scouring. For details on the project, maintenance and emergency works scheduled in your area, please visit Council's Facebook page.

From Galvanised Pipes

Corrosion may occur in older homes with galvanised pipes, causing the water to look orange or brown. Discolouration will occur more often in houses with galvanised water pipes. Galvanised pipes are no longer used in homes, with copper - or more recently polyethylene pipes have become the norm.

Anyone who experiences regular water discolouration and has galvanised water pipes in their home may consider replacing them and should seek further advice and assistance from a licensed plumber.

Any rectification works for galvanised pipes are at the customers expense.

Milky White Coloured Water

Water that is milky or white in colour is the result of small air bubbles within the water. This is usually due to air becoming trapped in the pipes - perhaps after the repair of a broken water main. This water is harmless and if left in a container on the bench, the air will quickly dissipate, and the water will become clear. It will not stain your washing.

Dirty Water and Laundry

Discolouration of the water supply by materials such as iron and/or manganese may cause a rust coloured stain on your light coloured clothing and linen while washing. If you notice a discolouration in the water from your household taps, it is recommended you do not wash clothing and linens in discoloured water due to the risk of stains.

If discoloured water is present, residents should delay washing clothes. If this is not possible, Council recommend:

  • running some water into the machine to check the water colour before washing clothes; and
  • checking the water colour before the washing machine reaches the rinse cycle – as it is at this stage that clothes can be stained.

If your load of washing is stained from dirty water, you should keep the washing completely wet, and not hang it out. The stain only becomes permanent if the laundry is allowed to dry. If you have a nappy stain remover then the affected washing should be soaked and washed as directed, this can often remove the stains once the water has been cleared.

Some washing powders cause the pH level of the water in the washing machine to increase, and this has the effect of causing manganese or iron in the water to come out of solution and to stain the washing. Also, powders high in phosphorus can also have the same effect.  A good quality liquid dishwashing detergent can also help remove dirty water stains

If your property, including clothes, household furniture or fittings, has been damaged by a dirty water (water discolouration) event, Council will consider on a case by case basis, requests to clean, replace or repair the damaged items.  Details on how to make a claim and the terms and conditions of damaged items due to a dirty water event are detailed in POL/26030 Water Supply Services Policy.

What should I do if I notice dirty water?

If you notice water discolouration in your home, we suggest you wait an hour or two then check that the water from your front tap (nearest to the water meter) is clear. If it is clear, go to the tap at the furthest point from your water meter (usually the garden tap in the backyard) and run the water for a few minutes until it also runs clear. 

If the water coming into your front tap is not clear contact Council and we can arrange flushing of the water mains in the local area. While flushing is being undertaken, customers can experience very dirty water, however this will clear shortly afterwards.

Council has approximately 300 kilometres of water mains, 9 water pump stations and 12 water reservoirs, so we are unable to monitor them all at the same time, so we do rely on residents to advise us of any severe or ongoing discolouration to the water supply in order to take action in the immediate area.



Earthy Odour and Taste - Geosmin

About Geosim

Seasonal increases in naturally occurring algae or bacteria in the dam, can sometimes cause odour and taste issues with drinking water, where the water is often reported as having an earthy or musty taste and smell.   This is due to harmless, naturally occurring dissolved compounds in the water, called Geosmin and Methylisoborneol (MIB) 

Human noses and tastebuds can detect Geosmin and MIB at very low concentrations. These compounds are sometimes present in drinking water, but not usually at noticeable levels. Changes in the temperature can increase some kinds of algae and bacteria naturally present in the water source (Glennies Creek Dam) that can cause a rise in Geosmin and/or MIB above the taste and odour threshold. 

 Unfortunately, Geosmin and MIB are not removed from water using routine treatment processes. However, the water is safe to drink and use for all normal purposes. Council’s water treatment processes are working normally with water quality results being consistently compliant with the Australian Drinking Water Guidelines. 

 In times when increased levels of Geosmin and MIB are present, extensive monitoring of the water quality occurs to confirm there are no health risks associated with the drinking water. Council may implement additional treatment processes, such as Powdered Activated Carbon (PAC) dosing to reduce these compounds, but it will not remove them completely.

Geosmin is only an aesthetic concern.  We do appreciate people’s patience and understanding in these events, as we continue to do everything we can to improve the taste and odour problems in our drinking water supply.

Geosmin and MIB and the Treatment Process

Council’s uses many treatment processes to remove algae, particulates and dissolved compounds from the water sourced from Glennies Creek Dam. 

To remove Geosmin and MIB, to below detectable odour and taste levels, activated carbon can be added as a pre-treatment, which is then removed as part of the filtration process.  Activated carbon is extremely porous and absorbs taste and odour compounds onto its surface. 

However, the amount of activated carbon needed to remove the levels of Geosmin and MIB below the odour and taste detection levels in some instances exceeds the design capacity of the water treatment plant.  In the event of detectable levels of Geosmin and MIB, water quality testing is increased and all treatment options available to Council are investigated.

Is the water safe to drink?

Yes, the potable town water supplied by Singleton Council, as the Local Water Utility, is safe to drink.  Our treatment processes are designed to remove any harmful toxins, algae and other organic matter or particulates.  All potable water we supply fully complies with all health based requirements in the Australian Drinking Water Guidelines, and extensive monitoring continues to confirm there are no health risks associated with the drinking water. 

Geosmin is only an aesthetic concern.

Why can I still taste and smell it is it is being removed?

Unfortunately, Geosmin has a very strong, unpleasant taste and odour, which is harmless. Sensitive individuals may still detect the odour of Geosmin at extremely low levels, as it has a taste and odour threshold of approximately 0.00001 mg/L (10 ng/L). In comparison, the taste threshold for chlorine is generally considered to be between 0.1 and 0.4 mg/L.

When will it be fixed?

Due to ongoing favourable conditions for algae growth it is not possible to predict how long the Geosmin and MIB will remain at high levels in the raw water. Once the algae level has declined, there may still be high levels of Geosmin in the water afterwards. As the weather cools, Geosmin levels typically decrease.  All treatment process options to reduce the effects of Geosmin and MIB on the drinking water supply are being investigated by Council.

Is there anything I can do to reduce the taste?

There have been reports that putting water in a jug in the fridge can help with any taste and odour issues. As well as adding lemon or fruit wedges (orange, mint, cucumber, watermelon, etc) to water to help mask the odour and taste.


Boil Water Alerts

What is a Boil Water Alert?

In extraordinary circumstances, it may be necessary to issue a notice to potable water customers that indicates the water supply is not suitable for drinking; this is known as a ‘boil water alert’. These instances may include detection of contamination in the potable water system, failure of the treatment process (including exceedance of critical control points) or poor raw water quality.

Under Section 22 of the Public Health Act 2010, the Chief Health Officer has the power to issue advice, for the benefit of the public, concerning the safety of drinking water and any possible risks to health. This advice may include a boil water alert. Council will issue the advice to the public in a form and manner directed by the Chief Health Officer.

Council may issue a boil water alert of its own discretion. However, before issuing a boil water alert, Council will consult with Public Health Unit (PHU) wherever possible. Once a boil water alert has been issued, Singleton Council will notify customers urgently and will use a combination of the contact and communication methods. Council will consult with the PHU before lifting a boil water alert. In lifting a boil water alert, Singleton Council will endeavour to communicate the information in the same way the alert was issued.

Council will consider providing alternate sources of water to affected customers, including bottled water, dependent on the scale and anticipated length of time the boil water alert is anticipated to last.

When is a Boil Water Alert recommended?

NSW Health recommends a Boil Water Alert when there is a known contamination of the water supply OR when there is a risk of contamination in the water supply. NSW Health and Boil Water Alert Protocols determine the procedure to be followed.

What can I drink during a Boil Water Alert?

You can drink tap water if it has been boiled at a rolling boil for one minute. Cool and store all boiled water in a covered container. Kettles with automatic cut-off switches are suitable and variable temperature kettles should be set to boil. If you do not wish to boil your water, you may choose to buy commercially packaged water for drinking.

I drank the water before I realised there was a Boil Water Alert. Am I going to get sick?

The Boil Water Alert has been recommended as a precaution. If you drank the water before hearing of the advice, your risk of becoming ill is low. However, if you begin to feel unwell you should seek medical attention. Advise your health care practitioner that you have consumed tap water during the Boil Water Alert.

During a Boil Water Alert, why are restaurants/food premises are still open?

When there is a Boil Water Alert, restaurants/food premises are given very specific guidelines from NSW Health as to how to operate. These guidelines will ensure that the foods being served to the public remain safe. The NSW Food Authority has a helpful fact sheet Guidelines for the use of Non-Potable Water in Food Businesses to assist food premises ensure their water supply is safe for food preparation and human consumption.

Can I use the water for other purposes?

You can use the water for bathing as long as you do not drink it. Supervise babies and children during bathing to ensure that they do not drink the water. Cool boiled water should be used for food preparation, brushing teeth, ice making.

How long is boiled water safe to drink?

As long as the water is protected from contamination, it should remain safe to drink. Once the water has been boiled, cover it and place it in the refrigerator for future consumption.

Can my pets drink the water?

Pets should be provided with cooled boiled water, or water from an alternate source until the Boil Water Alert is lifted.

Can I use my coffee maker?

Most residential coffee makers are not capable of maintaining high temperatures for a long enough period of time to make the water safe to drink, use boiled water to fill your coffee machine water tank and if connected to the mains supply do not use the coffee machine until the Boil Water Alert has been lifted. Be sure to clean the coffee machine thoroughly before use once the Boil Water Alert is over.

Coffee and tea can be made by using water that has been brought to a rolling boil for a period of one minute or bottled water. If using an automatic shut off kettle, make sure the water has boiled for one minute.

Can I use my activated charcoal filter system (i.e. Brita or other brand names) to treat my water during a Boil Water Alert?

No. These filters are not designed to remove contamination from an unsafe water supply. If you have run the water through your filter during the Boil Water Alert it could be contaminated. It is recommended that you discard the filter and replace it with a new one once the Boil Water Alert is over.


How do I safely prepare my baby’s formula during the Boil Water Alert?

Sterilise all bottles, rings, utensils and nipples in boiling water for two minutes. The water being mixed with the formula should have been boil at a rolling boil for at least two minutes, which will sterilise the water, prior to mixing with the formula and feeding.


Asbestos Cement Water Pipes

The condition of all water supply assets, including asbestos cement pipes is monitored closely and pipes are replaced prior to deterioration. The Australian Drinking Water Guidelines 2011 and World Health Organisation have not set a guideline value for asbestos due to the absence of evidence that asbestos is hazardous to health in water. Any asbestos fibres that potentially make their way into drinking water are not considered to be hazardous to human health.

Asbestos in drinking water may come from a variety of sources including asbestos cement water pipes. In Australia more than 33% of all water supplies are delivered using asbestos cement water pipes. In Singleton 14% of the 288km water supply network is made from asbestos fibre cement pipes installed between 1960 and the early 1980’s.

Council is gradually replacing asbestos cement water pipes as part of its asset renewal program.