In 1991, a typhoon flooded 100 km², destroying more than 30,000 homes and killing 52 people. To avoid this, Japan started to create underground canals to prevent these floods. Thus Tokyo and some metropolises in Japan are fully protected against flooding from rains, typhoons and tsunamis. Although the city is full of underground buildings and tunnels, they are almost invisible to those on the surface.
One such tunnel is the 4.5km Kanda River Underground Retention Basin in a tunnel that is 40 meters underground. This basin could hold up to 540,000 tons of water when Tokyo is hit by floods. In Osaka we have the Hiranogawa Reservoir, with 1.9km to prevent flooding. There are several other small underground facilities, but today we are going to talk about the largest in the world.
G-Cans - The Underground Temple
There are underground constructions in Tokyo that started in the 90s and have pillars that weigh 500 tons. In this case we are talking about the G-Cans Project, an underground facility to divert water located from Tokyo to the Edogawa River. This facility has turbines and 78 pumps capable of discharging more than 200 tons of water per second. There are 6.4km of tunnels, 50 meters below the surface and cost over 3 billion to build.
The site is used a few times a year, you can visit this underground temple for free from Tuesday to Friday for an hour and a half. For this you must register in advance on the website below. We will also leave the address of the place.
- Website: www.ktr.mlit.go.jp/edagowa/gaikaku/english/index.html
- Address: 2nd Floor at Ryukyukan reception, 720 Kamikanasaki, Kasukabe city, Saitama 344-0111
- Phone: +81 48-746-0748
