Why is my tap water cloudy?

Is your tap water cloudy or milky in colour? Discover the common causes of cloudy tap water in Australia, from harmless air bubbles to potential contaminants. Learn how to identify the cause, test your water safety, and fix the problem quickly. Clear up your water and your concerns!

Cloudy tap water in Australia is a common occurrence and is usually caused by several factors:

The most common cause of cloudy tap water in Australia is the presence of tiny air bubbles. These bubbles can occur due to:

• Trapped air in pipes after repair work
• Changes in water pressure
• Temperature differences when cold water from underground pipes is exposed to warmer temperatures

Air bubbles typically clear up within a few minutes as the water settles. To test if air bubbles are the cause, fill a glass with water and let it sit. If the cloudiness clears from the bottom up, it’s likely due to air bubbles.

Hard water, which contains high levels of dissolved minerals such as calcium, magnesium, and iron, can cause cloudiness in tap water. Some areas in Australia, particularly Brisbane, Adelaide, and certain towns in Western Australia, are known to have harder water than other regions.

Sediment or total suspended solids (TSS) can cause tap water to appear cloudy. This may include:

• Clay
• Iron
• Algae
• Other small particles

TSS can be more common after construction or disturbances near local water supplies.

Less common causes of cloudy tap water in Australia include:

• Methane gas (primarily affecting remote properties using bore water)
• High concentrations of nutrients, bacteria, pesticides, or metals in the water

Drinking cloudy water can have varying health implications depending on the cause of the cloudiness. It’s crucial to distinguish between harmless and potentially harmful contaminants to determine whether the water is safe for consumption.

Harmless contaminants include:

• Air Bubbles
• Hard Water

Cloudiness due to sediment or TSS should not be consumed without treatment. TSS can include clay, bacteria, and other small particles that may pose health risks.

Recent studies have found a link between cloudy tap water and outbreaks of gastrointestinal illness, even when the cloudiness was within allowed limits [1]. Waterborne pathogens like norovirus, Giardia, and Cryptosporidium can cause acute gastrointestinal illness (AGI) with symptoms such as:

• Diarrhea
• Vomiting
• Stomach cramps
• Nausea
• Headaches
• Fever
• Fatigue

In some cases, cloudiness may indicate the presence of chemical contaminants, which can have various health effects depending on the specific chemicals involved.

Identifying whether cloudy water is safe for drinking is crucial because:

1. Not all cloudy water is harmful, and unnecessarily avoiding it may lead to dehydration.
2. Consuming contaminated water can lead to serious health issues, especially for vulnerable populations like children, the elderly, and those with weakened immune systems.
3. Persistent cloudiness may indicate underlying issues with the water supply or plumbing system that require professional attention.

To determine if cloudy water is safe:

1. Let it stand in a glass. If the cloudiness clears from bottom to top, it’s likely due to harmless air bubbles.
2. If cloudiness persists, accompanied by unusual colour or odour, or if you’re unsure, it’s best to have the water tested or contact local water authorities like Sydney Water.

Temperature fluctuations can dramatically alter the clarity of tap water. Cold water holds more air than warm water, so tap water may appear cloudy or milky when first drawn. As water temperature decreases, its ability to hold dissolved gases increases. Conversely, warmer water releases these gases, leading to fewer air bubbles and clearer water. This is often a temporary condition, and the water will clear up as the temperature rises and trapped air escapes.

On a microscopic level, the dissolved air in cold water forms fine bubbles as the water warms to room temperature. These bubbles scatter light, giving the water a cloudy appearance. The process is similar to opening a carbonated beverage and seeing the fizz rise to the top as it warms and loses carbonation.

Addressing changes in tap water clarity due to temperature is a simple process. If the cloudiness dissipates after the water warms up, this indicates that the cause is not a major concern. However, persistent cloudiness, irrespective of temperature, may require further investigation into the water supply or plumbing.

To fix cloudy tap water in Australia, you can try several methods depending on the cause:

If the cloudiness is due to air bubbles, which is the most common cause in Australia, simply wait for a few minutes. The cloudiness should clear from the bottom up.

High water pressure can cause cloudiness. Consider having a plumber check and adjust your water pressure if the issue persists.

Run all taps in your home for several minutes to clear out any loose sediment that may be causing cloudiness.

1. Remove and clean the aerator (the screen at the end of the faucet / tap) with vinegar
2. Rinse thoroughly and reinstall
3. If cleaning doesn’t work, replace the aerator

Consider installing:

• A sediment filter to trap particles
• A water softener if you have hard water

If the cloudiness persists or is accompanied by discolouration or unusual taste, contact a professional plumber from North East Plumbing for an inspection and advice.

Remember, in most cases, cloudy tap water in Australia is harmless and safe to drink, especially when caused by air bubbles. However, if you’re concerned about water quality, it’s always best to call a licensed plumber.

[1] (2016). New Water Turbidity Measurement Technology – the US Experience.