How do you build a $2.6 billion underground city to stop a metropolis from drowning? Welcome to the G-Cans — Japan's Metropolitan Area Outer Underground Discharge Channel, the most advanced flood control megaproject in human history.
50 meters beneath the suburbs of Saitama, Japanese engineers constructed a 6.3km subterranean artery capable of swallowing an Olympic swimming pool every 3 seconds — protecting 11 million people from catastrophic typhoon flooding.
In this engineering documentary, we break down:
• The 59-metre underground cathedral cistern and its 500-tonne pillars
• How 5 giant silos intercept overflow from 5 rivers simultaneously
• The 14,000-horsepower pumps that drain a disaster in hours
• Why Tokyo floods in Japan have dropped by 95% since completion
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⚠️ IMPORTANT: ABOUT THIS VIDEO
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All visuals in this video are AI-generated conceptual representations created for educational purposes. This content is based on publicly available engineering and construction data. AI-generated narration and imagery disclosed in accordance with YouTube's synthetic media policy.
Music from #InAudio: https://inaudio.org/
Track Name. Life Goes On
Runtime 00:11:55
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