You can drink water in Tokyo from tap directly.

Production of potable delicious water with the power of ozone and biological activated carbon

Advanced Water treatment is a water purification method. Through this water treatment the strong oxidizing power of ozone and the adsorption/decomposition effect of biological activated carbon produce potable delicious water.
The musty odor substance, which causes bad taste in water, is broken apart by the action of ozone, absorbed by activated carbon and decomposed by microorganisms bred in the activated carbon.
This collaborated action enables production of delicious water by eliminating the odor substance.

We have introduced water treatment system at all the purification plants which purify the river water of the Tone River system.

Supplying safety under the through water-quality management

We control the tap water quality, setting higher than national standards.

Preserving rich forests in the basin area of Tama river

We properly manage forests in the Tama River Water basin area and by doing so protect our source of water supply with care. 

Tap Water in Tokyo is soft water, and the taste is mild

Tap water in Tokyo is soft water. The taste of soft water is mild, so Tap water in Tokyo is good for drinking!