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Did you know?

Why does my water...

We’re lucky to have some of the most pristine catchments in Australia, however customers may occasionally experience issues with their water quality. While these issues may affect the appearance, taste or odour of your water, most of them pose no risk to your health.

Some of the most common questions that customers ask are detailed here. It’s important to note that taste and smell is difficult to measure, as some people have a greater sensitivity than others.

We add chlorine to your water to kill unwanted micro-organisms, such as E.-coli, that may be present. Sometimes chlorine reacts with organic matter in the pipes and creates a noticeable taste or smell. It can often be more obvious after pipes have been flushed as part of our ongoing maintenance schedule.

The chlorine concentration is generally very low (less than one part per million) and can be reduced further by letting the water sit in the fridge in an open jug for a short period prior to consumption, or by installing a household filter.

Water can look brown or muddy when there is sediment in the pipes. This is often due to a scheduled flushing program to clear any sediment build-up or discolouration in water mains near your property.

However, it could also be due to a burst water main close to your property. Generally these happen unexpectedly, and our maintenance team responds as soon as possible to restore services to customers. If you notice a burst, please contact our 24 hour hotline on 1300 926 666 to report the location.

An earthy or musty taste and odour can be caused by build-up of sediment and organic matter in our network or in the interior plumbing at your property.

Occasionally, naturally occurring organisms in our raw water storages can cause earthy or musty tastes and odours, particularly during hotter months. When this occurs, the water supply may be impacted.

If you experience an earthy or musty taste or smell, run one of your taps for a few minutes to flush any older water through your home's pipes.

If the problem persists, please call us on 1300 926 666 so we can investigate and take action as soon as possible.

It may be due to seasonal compounds such as Geosmin and Methylisoborneol (MIB) or cyanobacteria (commonly known as blue-green algae).

We regularly monitor our water storages for the presence of algae, Geosmin and MIB. If the levels rise higher than usual, we work to resolve the issue with actions that may include changing the source of the water, adjusting the treatment process or flushing our network.

Despite the smell and odour, the water is still perfectly safe to drink and complies with the Australian Drinking Water Guidelines. Using a jug-type filter or similar can help if you find the water too unpleasant.

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 that are naturally present in our water sources. This can cause a rise in Geosmin and/or MIB above the taste and odour threshold.

Unfortunately, although harmless, they can cause a very strong, unpleasant taste and smell. People who are sensitive may still be able to detect the odour at extremely low levels.

We appreciate people’s patience and understanding as we work to resolve the issue.

Blue green algae

Blue-green algae (cyanobacteria) are naturally occurring bacteria which are found in the majority of waterways and reservoirs. There are a number of different species (toxic and non-toxic) that can produce taste and odour issues.

Hot weather, high nutrient levels and slow flowing water in reservoirs can provide optimal conditions for algae to flourish and rapidly increase in numbers. This can make the water smell earthy or musty. We do our best to remove these odours in our treatment plant, however some people may still notice a faint taste or odour in their drinking water.

Taste and odour causing substances produced by algae only affect the aesthetics of the water and are harmless. The water is still perfectly safe to drink.

Air can enter the water supply following repairs to our pipe network – for example, after we have carried out maintenance work or fixed a burst main. It can also occur when a pocket of air becomes trapped in the pipework inside your home.

Water with air in it has a cloudy or milky white appearance, caused by the concentration of thousands of tiny air bubbles. This can take several minutes to clear, and will do so from the bottom of the glass upwards.

You may also notice that the water splutters out of the tap, which is again caused by trapped air in the pipe. This is quite normal and harmless, and the problem should clear if you run the tap for a few minutes.

If your water is an orange/brown colour when you first run your tap but clears after a short period, or if it tastes metallic and bitter, this usually indicates high levels of iron or copper. Both can leach into your water from corroded pipes.

Corrosion can occur when the plumbing is old, particularly with cast iron or copper pipes. In some instances, it can only take a small length of pipe to produce the discolouration.

Running your taps for about 30 seconds to draw fresh water through may resolve the issue. If not resolved, a pipe burst or leak can occur. Consult a plumber for advice

Water with very low levels of dissolved oxygen will develop a septic/rotten egg odour, but this should not happen in your drinking water. The most common cause of this type of problem is the drain.

Over time, organic matter such as hair, soap and food waste can accumulate on the walls of the drain. Bacteria can then grow on that organic matter. What you can smell is the gas produced by the bacteria.

You will be more likely to smell the rotten egg odour when water from the shower or kitchen tap runs over the drain.

You can alleviate this smell by rinsing your drain with a strong disinfectant bleach.

Hardness levels depend on the natural mineral deposits (i.e. rocks and soils) from the catchment that supply our water. It is measured by the amount of calcium carbonate in water in milligrams per litre (mg/L).

The Australian Drinking Water Guidelines (2011) have a scale of water hardness as it impacts on water quality. Water less than 60 mg/L is regarded as “soft”, while water higher than 200 mg/L is described as “hard”.

Our supplies range from an average of 14 mg/L in towns supplied by a surface water catchment to 440 mg/L in towns where the water is sourced from the ground.

The quickest way to work out whether your water is hard is to try to lather soap. If it doesn’t lather up, your water is hard. If it lathers extremely easily, then it is soft.

When hard water is heated, the minerals that cause hardness come out of the water and are deposited as scale. This can affect kettles, hot water services, dishwashers, pipes and fittings. Scale is harmless, but over time it builds up.

The most common way to reduce the build up of scale is keeping hot water systems below 60 degrees Celsius.

More information is available in our Water Hardness Information Sheet.

Sudden changes in your water pressure could be due to planned or emergency works in your local area. Normal water pressure will be restored when the work is complete.

If your pressure is regularly low there may be other causes. Consult a plumber for advice.

We add fluoride to our drinking water to prevent dental decay, as directed by the Victorian Government and endorsed by the National Health and Medical Research Council (NHMRC).

Water supplies in Warrnambool, Allansford, Koroit, Hamilton, Dunkeld, Tarrington, Camperdown, Lismore, Derrinallum, and along the Camperdown rural pipeline all have fluoride added.

The Department of Health (DoH) has directed us to fluoridate the water at the Terang WTP. This will mean customers served by the Terang WTP (Terang, Noorat, Glenormiston and Mortlake) can expect to receive fluoridated water by late 2023.

The water in Portland and Port Fairy contains naturally-occurring fluoride Other supply areas are not currently connected to a fluoridated supply.

The addition of fluoride to our drinking water is carefully controlled and monitored, and doesn’t change its taste, smell or colour. Fluoride is added to an optimum dosage of one part per million (one milligram per litre), as declared by the NHMRC.

More information is available from the Department of Health.

We produce a Drinking Water Quality Annual report each year. For more information, visit the Annual Water Quality Reports page.

If you remain concerned about your water quality, don't just ask yourself why? Follow it up with us on 1300 926 666 and we’ll try and work through a solution with you. We're here to help.