Tokyo has constructed the world's largest underground flood tunnel, a $2 billion engineering feat designed to protect the city from severe flooding. This enormous tunnel is so large that it can accommodate a space shuttle, highlighting the scale of the infrastructure. Since its completion, the tunnel has significantly decreased flood damage in the area, with local flooding reduced by about 90%.
The project represents a major investment in disaster prevention and showcases Japan's commitment to innovative solutions for urban safety. This flood control system is a critical component of Tokyo’s broader strategy to mitigate the impact of natural disasters, protecting both residents and infrastructure from the effects of heavy rainfall and potential floods.