Even though tap water in Tokyo is perfectly safe to drink, and in most cases indistinguishable from bottled water, the metropolitan government is concerned about the bad rap it gets from citizens who will not give it a try. In October, the Bureau of Waterworks, charged with providing clean and tasty water for Japan’s largest metropolitan area, wrapped up a 25-year-long project to connect the majority of Tokyo residents to great-tasting and specially treated water from the Tone River system.
According to an NHK article, the government agency wants to get the word out that their water is just as good as any store-bought bottled water and has asked 700 private citizens all over Tokyo to become “water monitors” and test their home’s tap water for minerals and judge its quality.
The Tokyo government has had plenty of complaints about its water in the past when customers frequently called in to express their displeasure with the “inferior quality” of the nastiness coming from their taps. (They should see how things are in other countries…)
To improve the taste of Tokyo, the water authority started a massive project back in the 1980s to place advanced treatment water facilities in five areas around Tokyo.
▼ A map from the water bureau shows the dark blue areas in Tokyo that are 100% connected to the network of advanced water treatment plants that get water from the Tone River. Areas in the west that already have quality water sources are shown in light blue, and grey areas are localities not connected to Tokyo’s water network.
Image: Tokyo Bureau of Waterworks
In addition to the normal treatment process, these plants would also add an extra purification step where disinfecting ozone would be added to the water to kill odor-causing bacteria. Activated charcoal is also added to encourage bacteria-eating microorganisms to breed. With the addition of the ozone and charcoal, the water agency can reduce the amount of chlorine, improving the water’s smell and taste.
▼ A diagram of the water purification process, with the “advanced” steps of adding ozone and activated charcoal shown below
Image: Tokyo Bureau of Waterworks
But even with all that hard work, changing people’s minds about tap water is apparently harder than rerouting rivers and sanitizing the water supply for one of the world’s most populated cities. Of course, there are many reasons your water may taste bad, such as a bad water filter or poor plumbing at your apartment, but Tokyo really wants its water to have a better reputation.
When the Tokyo government polled about 3,600 people and businesses, only 52% said they were satisfied with their city’s water and 16% said they were dissatisfied. Not surprisingly, the main reason people gave was that they did not like the taste of tap water.
And since the best way to respond to this issue is to rally public opinion in your favor, the government agency will be starting an amateur water monitoring system in the next few weeks to have its own citizens prove the excellency of Tokyo water. About 700 of these monitors will soon be observing and recording the quality of their home’s tap water to show on the water bureau’s webpage for all to see.
The monitors will have a test kit and be able to detect different levels of minerals in the water and also be asked to judge their water’s taste and smell. The Tokyo government hopes that by people seeing a visualization of their tap water quality, it will inspire more of its residents to forgo bottled mineral water and drink from the tap, which is something we’re sure the environment will also thank them for.
▼ An example of the website where blue dots represent the 700 monitors’ locations and each entry shows the readings for acceptable levels of chlorine, water hardness and iron.
Image: Tokyo Bureau of Waterworks
▼ A closeup of one of the water monitors’ testing kits
Image: Twitter (tocho_suido)
How clean is the water in your town? Are you a bottled-water-only kind of person? Let us know in the comments section below!
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