Why your tap water tastes different from house to house

If you've ever moved house — or just filled a glass at a friend's place — you'll know that tap water doesn't taste the same everywhere. Same city, sometimes even the same street, and yet one kitchen tastes clean and another tastes faintly of a swimming pool. Here's what's actually going on.

It's (almost always) chlorine

Australian water authorities add a small amount of chlorine to keep water safe all the way from the treatment plant to your tap. It works — our tap water is among the safest in the world. But chlorine has a taste and a smell, and how much you notice depends on how far you are from the plant, the time of year, and how long the water has been sitting in the pipes.

Then there are the pipes

The last few metres matter more than people think. Older buildings, long runs of pipe, a bit of sediment, an ageing hot water system — each one can add a metallic edge or a flat, dull taste. None of it makes the water unsafe. It just makes it taste like less.

What you can do about it

You don't need to buy bottled water, and you definitely don't need to panic about safety. A simple activated-carbon filter on the tap reduces the chlorine, sediment and odour that carry most of the taste — so the water tastes the same clean way no matter whose kitchen you're standing in.

That last part is really why NERŌ exists: a constant glass of good water, wherever your tap happens to be.