Watch... This is how Japan protects millions of residents from floods
Underground flood control facilities are very important engineering structures in many major cities, as they serve to prevent floods and protect the cities and surrounding areas from flood damage. These facilities typically have huge tanks and complex drainage systems to store and channel water and relieve pressure from heavy rains. Japan's underground metropolitan area drainage canal is an amazing engineering feat. Built to address Tokyo's flooding problems, it includes a complex network of tunnels, pipes and tanks to control water flow. This facility acts as a kind of guardrail to prevent flooding in the city. Using these facilities to store and direct water helps avoid catastrophic flooding and reduce damage that may occur as a result of heavy rains and severe storms.
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