Key Points
- The Metropolitan Area Outer Underground Discharge Channel, one of the world’s largest flood control systems, was activated to manage heavy rainfall in Saitama Prefecture.
- Footage shows water from several rivers, including the Nakagawa and Tone, being diverted into massive underground shafts.
- The system utilizes five shafts, each large enough to fit a Space Shuttle, connected by a 6.3-kilometer tunnel.
- Water eventually collects in a “pressure adjustment tank” before being pumped safely into the Edo River.
Full Transcript (English)
(Text on screen): Tone River System, Metropolitan Area Outer Underground Discharge Channel. Inflow into Shaft No. 2. Please be careful of the volume.
(Text on screen): Kanazaki, Kasukabe City, Saitama Prefecture. Shaft No. 2, 18th waterway inflow part 2.
(Text on screen): Inflow into Shaft No. 3. Shinkawa, Kasukabe City, Saitama Prefecture. Shaft No. 3, Nakagawa Gate.
(Text on screen): Higashiyashio, Kasukabe City, Saitama Prefecture. Shaft No. 3, inflow part (Nakagawa).
(Text on screen): Oootoshifuru Tone River.
(Text on screen): Shaft No. 5, inflow part (inside the shaft).
(Text on screen): Inflow into Shaft No. 1. Kamikanazaki, Kasukabe City. Shaft No. 1, pressure adjustment tank inflow part.
(Text on screen): 120x speed.
(Text on screen): Inflow into the pressure adjustment tank. Kamikanazaki, Kasukabe City. Showa Drainage Pump Station, pressure adjustment tank (inflow) 2. 144x speed.
