| The Metropolitan Area Outer Underground Discharge Channel (Japanese: 首都圏外郭放水路, Hepburn: shutoken gaikaku hōsuiro), popularly known as G-Cans, is an underground water infrastructure project in Kasukabe, Saitama, Japan. It is the world's largest underground flood water diversion facility, built to mitigate overflowing of the city's major waterways and rivers during rain and typhoon seasons.[1] It is located between Showa and Kasukabe in Saitama prefecture, on the outskirts of the city of Tokyo in the Greater Tokyo Area. |
