Why drink water?
Drinking plenty of water is very important for good health. Being properly hydrated helps your body function at its best. Most people in NSW receive good quality drinking water that is safe to drink. Although some variation in the quality of drinking water will occur because of the different sources of water used and different forms of treatment, drinking water that meets the Australian Drinking Water Guidelines (the Guidelines) is considered safe to drink.
The Public Health Act 2010 requires all drinking water suppliers to implement a quality assurance program for the safe supply of drinking water. Public drinking water supplies in NSW are routinely monitored. In regional areas, local water utilities (generally the local council) supply the drinking water and monitor in proportion to the size of the population and the area supplied, as outlined in the Guidelines. NSW Health has a comprehensive Drinking Water Monitoring Program for water utilities in regional areas.
Bottled water is not necessarily any safer than your local drinking water supply.
Can I find out about my drinking water quality?
Yes. Your water utility can provide water testing results. NSW Health encourages all public water suppliers to regularly report water quality information to their consumers. Water quality results from across NSW are available in the NSW Department of Industry Water Benchmarking report (Table 5).
Sydney Water and Hunter Water publish drinking water monitoring results on their websites.
What are the Australian Drinking Water Guidelines?
The Australian Drinking Water Guidelines, published by the National Health and Medical Research Council (NHMRC) and the Natural Resource Management Ministerial Council are an authoritative Australian reference on good quality drinking water. The Guidelines are regularly reviewed by the NHMRC in consultation with the general community, health bodies, water suppliers, and regulators.
What substances are found in water?
There is no such thing as naturally pure water, all water contains some impurities. As water flows in rivers, is captured in dams and filters through layers of soil and rock in the ground, it dissolves or absorbs a range of substances. Most of these substances are harmless. However at certain levels, some substances are considered contaminants that can make water unpalatable or even unsafe.
What chemicals are added to the water and why?
Water utilities disinfect drinking water with chlorine to kill microorganisms that may cause disease. Chlorine is a very effective disinfectant that has been used for many years. Many water utilities also fluoridate 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.
To remove the chlorine taste 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 alum and ferric chloride, are reduced to very low levels before leaving the treatment plant.
Illness associated with drinking water
NSW Health regulates drinking water quality, monitors cases of infectious diseases in the community, and investigates outbreaks to determine their cause. Common causes of diseases that infect the gut include contact with infected persons (including in childcare centres, by not washing hands after going to the toilet and after changing nappies), consumption of contaminated foods, bathing in contaminated swimming pools, and contact with animals (particularly young livestock) that may carry these diseases. These diseases may also be spread through contaminated drinking water, although such events are now very rare in Australia.
Incidents and warnings to the public
Occasionally incidents affect drinking water quality. These may include changing source water conditions such as flooding, operational problems, detection of Escherichia coli bacteria and/or blooms of cyanobacteria (blue green algae). In some cases there may be a need to issue a notice advising a community to boil their drinking water 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, such as with an automatic kettle, allowed to cool and stored in a clean container with a lid and refrigerated.
Householders in affected areas should use boiled water for drinking, cooking, washing raw foods (such as seafood or salads), making ice, pet’s drinking water, and cleaning teeth or gargling. Children should take boiled or bottled water to school. Dishes should be washed in hot soapy water or in a dishwasher.
Using water in the home
Use water from the cold water tap for drinking and cooking. Hot water systems may contain more dissolved minerals and metals, due to the heating process.
Copper pipes are used extensively in plumbing systems in Australia (and internationally). Drinking water can contain elevated metals such as copper and sometimes lead when left standing in pipes for extended periods. In this case, it is a good idea to flush cold taps for 2-3 minutes before using the water for drinking or cooking. This will lower the levels of copper and other metals that may be present in the water. This ‘first-flush’ of water can be used for washing up, watering plants, or other non-drinking uses. The Environmental Health Standing Committee (enHealth) also recommends 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 (see enHealth Guidance Statement - Lead in drinking water from some plumbing products).
What about filtering tap water?
There is generally no need to filter tap water that has already been treated – it should be safe to drink. However, if filters are used to improve taste, it is important to maintain and replace them regularly otherwise they will become ineffective. It is important to follow the manufacturer’s instructions.
Not all filters remove or inactivate harmful microorganisms. If a filter is used it should be certified against an appropriate standard (such as AS/NZS 4348:1995 and/or NSF/ANSI 42 and 53). An absolute 1 micron (or smaller) filter is necessary to remove Cryptosporidium and Giardia. Units that incorporate boiling, distillation or reverse osmosis processes are also satisfactory. An additional disinfection unit may be necessary to inactivate bacteria and viruses.
Who can I contact for additional information?