Are you cleaning your water filter regularly?

Media release

5 May 2017

Around 38% or 684,000 households across Greater Sydney, the Blue Mountains and the Illawarra use a water filter device of some type.

According to a customer survey conducted by Sydney Water, more than half of the households who have water filters claim not to change the cartridge in their filter as regularly as the manufacturer of the filter recommends.

Dr Peter Cox, Principal Advisor on Public Health at Sydney Water, said 'Sydney Water has some of the best quality drinking water in the world and there is generally no need to filter tap water as it has already been treated and filtered by us and it is completely safe to drink.

The majority of Greater Sydney households, all 1.2 million of them, drink their water straight from the tap.

Sydney Water filters all the water before it gets to household taps and we clean our filters every few days. It is far safer to drink water straight from the tap than from a filter using an out-of-date cartridge. Drinking water straight from the tap is also much cheaper than buying a filter.

If customers choose to use a water filter, it is important to maintain and replace the filter cartridges regularly, otherwise the filters will become ineffective.

It is also important to follow the manufacturer’s instructions because if you use a filter and don’t change the cartridge often enough, it can harbour bacteria and other micro-organisms, which defeats the purpose of using a filter in the first place, and this can create a health risk.

Be cautious of advertising claims made by water filter suppliers that unfiltered tap water is not safe to drink. Such statements are untrue for Greater Sydney and these statements are generally based on the standard of water supplies overseas or an exaggeration of the performance of their product', said Dr Cox.


Filters perform a variety of different functions, different filters filter different things and they can vary enormously in price.

The frequency of changing your filter cartridge will depend on how much water you consume. The more you consume, the more often you will have to replace or clean the filter cartridge.

If you feel you need to purchase a water filter, ensure that it is certified against an appropriate standard (such as AS/NZS 4348:1995 and/or NSF/ANSI 42 and 53).