Should we be drinking water from the tap?

Hot or cold – can you drink water out of the tap on a hot sunny day? People get confused about drinking warm water from the tap on hot days.

An expert on the subject, Professor Oliver Jones, Professor of Chemistry and Deputy Director of the RMIT Effective Technologies and Tools Research Centre, corrects the record.

‘People may have heard the advice not to drink hot water straight from the tap, this is said because hot water can dissolve minerals from the pipes better than cold, and also as bacteria tend to grow better in warm water.

Professor Oliver Jones says that, although there is only a very small risk, it can be reduced further by drinking from the cold tap. ‘However, people should ideally only drink from the kitchen tap rather than the shower or bathroom taps – and definitely not the garden hose.

Run the water for 10 seconds

‘If people are worried about things growing in their taps in summer, a good tip is to run the water for 10 seconds* or so – which will flush anything that’s been sat there for a while.’

Professor Oliver Jones said some people also worry about water contaminated by disinfection by-products – which can occur when disinfectants, like chlorine, interact with natural organic materials in water. ‘These are very strictly monitored. In a study a few years ago, an RMIT PhD student found the levels of disinfection by-products in Melbourne tap water were almost non-existent.

‘Either hot or cold water will keep you hydrated, and Melbourne has some of the best drinking water in the world.’

* You can run it into a container to water plants

Oliver Jones is a Professor of Chemistry, Deputy Director of the RMIT Effective Technologies and Tools (WETT) Research Centre and internationally recognised expert in analytical chemistry. He is passionate about using science to keep our environment safe.