Japans $3.2 billion dollar project to eliminate flooding There is something cathedral-like about Japan’s huge underground storm drain. The G-Cans – or, to use its official title, the Metropolitan Area Outer Underground Discharge Channel – comprises a labyrinth of tunnels that stretch on for four miles in total, connecting gargantuan 213ft silos with a tank that is almost 250,000 cubic feet in volume. The sacred feeling of the space was not lost on its designers, who nicknamed this tank the Underground Temple. The G-Cans was constructed in Kasukabe, a city some 20 miles north of Tokyo. Nestled 165ft below ground between the two cities, a visitor would have no way of knowing the mammoth storm drain was there. But this invisible system serves a critical function: the densely urbanised area is low-lying and has several rivers running through it, making it highly prone to flooding. The G-Cans was built with the capacity to drain 7,000 cubic feet of water per second – the equivalent of drying out an Olympic-sized swimming pool in just over 12 seconds. The water is then pumped into the Edogawa River on the outskirts of the city. This invisible system serves a critical function: the densely urbanised area is low-lying and has several rivers running through it, making it highly prone to flooding Every summer, Japan is battered by heavy rains and typhoons. These storms can cause extensive damage and loss of life. Among the most impactful in recent history was the 1959 Isewan Typhoon, which resulted in more than 5,000 deaths. For decades, Kasukabe consisted mainly of farmers’ fields, which meant that any damage incurred by a flood was relatively minor on the national scale. But towards the end of the 20th century, Kasukabe became more urbanised and heavily populated as Tokyo expanded. It was in 1991, when a storm damaged 30,000 homes in the northern outskirts of the Japanese capital, that authorities were persuaded to invest in more protection. - @vivesarchive