A year after torrential rains hit western Japan, newly disclosed data by the Fukuoka Prefectural Government showed that massive inland flooding of the six tributaries flowing into the Chikugo River in the prefecture occurred because the amount of rain that fell is estimated to be about three to 10 times the capacity of the pumping systems.

Experts point to the difficulty of building infrastructure that can completely prevent disasters triggered by climate change, saying that the most effective way to protect one's life is to evacuate at an early stage.

On July 6 and 7 last year, as the Chikugo River and its tributaries began to swell simultaneously, the tributaries' floodgates were closed to prevent water from flowing back from the main stream. But the tributaries' pumping systems failed to discharge the rainwater, resulting in the streams breaching their banks and flowing into farmlands and residential areas in the city of Kurume and surrounding areas.