Drinking water and public health

Why drink water?

Water is essential for health. Being hydrated helps your body function at its best.

How is drinking water quality managed in Victoria?

Victoria's drinking water provided by water suppliers is managed under a comprehensive regulatory framework. This safe drinking water regulatory framework aims to ensure a consistent, reliable supply of safe, good quality drinking water.

Victoria's Safe Drinking Water Act 2003 requires all drinking water suppliers to implement, develop and review risk management plans to manage risks to drinking water. This includes the treatment and sampling of water. These risk management plans are subject to an independent audit at intervals determined by the Department of Health and Human Services (the department).

The drinking water that is provided by water suppliers meets the objectives of the Australian Drinking Water Guidelines (the Guidelines) and is safe to drink.

The water supplier is responsible for the main water infrastructure and quality of drinking water prior to the property meter. The property owner is responsible for maintaining internal plumbing from the property meter.

Can I find out about my drinking water quality?

Yes, drinking water supplies are routinely monitored by water suppliers at designated sampling locations. Water quality monitoring information is made publicly available by your water supplier. Water suppliers publish annual reports on the quality of the drinking water they supply; many also publish drinking water quality monitoring results on their websites. You can request further water quality information from your water supplier. More information about drinking water in Victoria can be found on the Drinking water in Victoria page on health.vic.

What are the Australian Drinking Water Guidelines?

The guidelines, published and maintained by the National Health and Medical Research Council and the Natural Resource Management Ministerial Council, are an authoritative reference on safe, good quality drinking water. The guidelines are based on the best available scientific evidence and provide a framework for good management of drinking water supplies to ensure safety at point of use.

What is naturally found in water?

As water flows in rivers, it is captured in dams and filters through layers of soil and rock in the ground, and dissolves or absorbs a range of substances. Most of these substances are harmless. However at certain levels, some substances can make water unpalatable or even unsafe. Natural sources of water may contain harmful microorganisms from animals and humans. This is why most natural sources of water are treated prior to drinking.

What chemicals are added to drinking water and why?

The guidelines specify approved chemicals for use in water treatment. Water suppliers filter and disinfect drinking water with chlorine and other treatment methods to kill microorganisms that may cause disease. Chlorine is an effective disinfectant that has been used safely in water supplies for many years. Many water suppliers also add fluoride to the water to protect against tooth decay. Both of these chemicals are added in carefully controlled amounts and their levels are monitored to ensure they meet health guidelines.

Some people are more sensitive than others to the taste and odour of chlorine. To remove the chlorine from drinking water, allow a jug of water to stand for a few hours before drinking.

The chemicals used as part of the filtration treatment process, such as aluminium sulphate and ferric chloride, assist in removing particle matter in water. These chemicals are reduced to very low levels before leaving the water treatment plant.

Victorian water suppliers are required to report annually on the quality of the drinking water supplied, this includes reporting on the chemicals added to drinking water.

Responding to water quality issues

Occasionally, incidents such as floods, bushfires, blooms of cyanobacteria (blue-green algae) and treatment plant operational issues may affect drinking water quality.

If an incident presents a potential risk of microbiological contamination there may be a need for a water supplier to issue a notice advising a community to boil their drinking water before consuming, or to take other precautions. If your water supplier has issued a boil water notice it is likely to be due to microbiological contamination.

When a notice is issued, drinking water should be brought to a rolling boil. Boiling the water will kill harmful microorganisms present. Care should be taken to avoid scalding injuries. Allow the water to cool and store it in a clean container with a lid and refrigerate. Householders in affected areas should use the boiled water for drinking, cooking, washing raw foods (such as seafood or salads), making ice, drinking water for pets, and cleaning teeth or gargling. Children should take boiled or bottled water to school. Dishes can be washed in hot soapy water or in a dishwasher.

Using water in homes, buildings and public places

In the home

Reticulated drinking water coming into homes and buildings is managed under the safe drinking water regulatory framework. In some cases water can sit in internal plumbing for extended periods of time, typically overnight or after holidays. This stagnancy may increase the likelihood of metals that are present in some plumbing products, such as copper and lead, leaching or dissolving from them. For example, lead can dissolve into drinking water from some brass plumbing fittings and copper can dissolve into drinking water from copper pipes. Fittings such as sinks and shower bases can be stained blue or brown by water. This is generally a reflection of the type of internal plumbing material present (for example, copper pipes or galvanised iron). Hot water systems may contain more dissolved minerals and metals due to the heating process.

Householders can proactively reduce their potential exposure to metals in drinking water through the following measures:

• using water from cold taps only for drinking, food preparation and cooking
• flushing cold water taps used for drinking and cooking for about 30 seconds first thing in the morning to draw fresh water through the tap
• flushing cold water taps used for drinking and cooking for about 2-3 minutes after long periods of non-use, such as return from holidays; this 'flushed' water can be collected and used for washing up, watering plants or other non-drinking uses.

Do not drink water that tastes, smells or appears different; you should contact your water supplier for advice.

Building and asset managers

For facilities such as healthcare facilities and schools, consult the building manager on the type of plumbing and optimal management regime for removing water that has been sitting in plumbing for extended periods of time. If water sampling and analysis is undertaken, this should be conducted by a certified laboratory.

Public drinking water fountains and publicly accessible taps

In the case of public drinking water fountains and publicly accessible taps, water may be sitting stagnant. It is therefore good practice to flush public drinking water fountains and publicly accessible taps for about 30 seconds to draw fresh water to the outlet.

What about filtering tap water?

There is generally no need to filter tap water that has already been treated. However, if filters are used to improve water taste or odour, it is important to maintain and replace them regularly otherwise they will become ineffective.

Filters should not be viewed as permanent solutions as they will require maintenance and replacement. Buyers of filtration devices should look for filters that are certified to appropriate standards and are fit for their chosen purpose. The filter manufacturer's instructions should be followed.

Private drinking water supplies

Some homes and buildings are unable to access a mains water supply and rely on a private drinking water source, such as rainwater tanks and bores. These water supply systems must also be managed effectively to reduce the risk of harmful microorganisms and chemicals being present in the water.

The department provides a range of resources related to managing public health risk associated with private water supplies. More information can be found on the Private drinking water section on health.vic.

Who can I contact for additional information?

• Your local water supplier can provide information on the quality of water supplied to you.
• health.vic's Water page provides information on drinking water quality.
• The Better Health Channel provides information on lead exposure and your health.