Web users across China have been shocked this week to see images of a flooded subway in the eastern Japan city of Hamamatsu. However, it was not the damage caused by Tropical Storm Etau which sparked discussion, but the cleanliness of the flood water that filled the underground walkway.

Flooded subway in Japan. Photo: Weibo.

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Images of the flooded subway quickly went viral on Chinese social media, attracting a level of nationwide attention that would most likely have perplexed locals.

Many web users compared the clarity of the water to that of a swimming pool—although considering that over half of Beijing swimming pools recently tested positive for excessive levels of urine, others went a step further, admitting that “even our swimming pools aren’t this clean.”

‘Underground swimming pool.’ Photo: Weibo.

“In China,” one netizen remarked, “[the water] would be like black sesame soup.” Some even insisted that the water in the images “is not scientific” and “must be Photoshopped.”

Flooded subway. Photo: Weibo.

Flooded subway. Photo: Weibo.

Keen to defend their own country’s hygiene record, some Chinese netizens even came up with a theory to explain why Japan’s flood water is so clean: “islands have less mud, so of course they’re cleaner than somewhere with many mountains and rivers. You can’t compare such a different geographical environment to China.”

Not everyone was convinced by this argument, however: “Japan also has crops and trees. According to your logic, they must plant them in sand.”

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