
Work on the project started in 1992 and was completed by early 2009. It consists of five concrete containment silos with heights of 65 m (213 ft) and diameters of 32 m (104 ft). It is connected by 6.4 km (4 miles) of tunnels, 50 m (164 ft) beneath the surface. There is also a large water tank (shown above) with a height of 25.4 m (83 ft), a length of 177 m (581 ft), and a width of 78 m (256 ft). There are 59 massive pillars connected to a number of 10 MW pumps that can pump up to 200 tons of water into the Edogawa River per second.










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