With the sheer number of vending machines in Tokyo selling bottled water, you’d be forgiven for thinking there was something wrong with drinking water straight from the tap. The good news is, there’s not; Tokyo’s tap water is safe to drink, and millions of people do so daily, unboiled and unfiltered.
Tokyo’s water is subject to stringent standards set by the Tokyo Metropolitan Government Bureau of Waterworks and must meet more than 50 water quality standards to be considered safe to drink, such as being free of pollution and harmful contaminants. The Bureau of Waterworks manages and protects the forests around the Tama River, Tokyo’s water source, and ensures water is purified through a combination of ozone and charcoal treatment. This removes pollutants, reduces odour and taste, and removes organic and inorganic matter. As water quality is ensured at the source and not the outlet, you can drink the tap water not just in homes but metro stations, malls and convenience stores – unless the signs say otherwise.
If the water tastes different to you at first, it could be because Tokyo’s water is ‘soft’ (low pH, low mineral content), whereas much of Europe and North America has ‘hard’ water (high pH, high mineral content). Soft water is known for its gentle flavour and aroma, and it’s thought that prestigious Tokyo cuisine owes some of its appeal to this soft water, which works well in mild, clean-flavoured dishes like dashi and tofu. Soft water is also recommended for brewing Japanese tea, as it’s believed to help reduce bitterness and astringency.
The average human needs two litres of water per day, as hydration is critical for brain and bodily function. Yet to turn on the tap and fill a glass of water – then drink it – is a luxury afforded by just a handful of countries in the world, so you shouldn’t take it for granted. By drinking tap water, you’re also reducing the need for single-use plastic water bottles, which are harmful to the environment. So when you're out and about, carry a reusable water bottle with you and check the MyMizu app for the best places to refill for free around Tokyo.