Introducing the Metropolitan Area Outer Underground Discharge Channel of Saitama Prefecture

This video, titled "Metropolitan Area Outer Underground Discharge Channel [Saitama Prefecture Official Sightseeing Video]" (首都圏外郭放水路【埼玉県公式観光動画】), was released by "Chokotabi Saitama."

The Metropolitan Area Outer Underground Discharge Channel, also known as the "Underground Parthenon," is one of the largest underground drainage channels in the world, designed to protect the eastern area of Saitama Prefecture from floods.
The Metropolitan Area Outer Underground Discharge Channel is a tunneling shield constructed using the muddy-shield type method, and boasts a length of about 6.3 km with an inner diameter of about 10 m.
Enjoy the video of the beautiful underground drainage channel, reminiscent of a temple, in Kasukabe City, Saitama Prefecture.

A Closer Look at the Metropolitan Area Outer Underground Discharge Channel Introduced in the Video

Photo：The Metropolitan Area Outer Underground Discharge Channel, Saitama Prefecture

The Metropolitan Area Outer Underground Discharge Channel is a flood protection facility built by the Ministry of Land, Infrastructure, Transport and Tourism; and Kasukabe City is in charge of its maintenance.
It began being used in June 2006.
The official nickname is "Sairyu no Kawa" (the River of Sairyu) but it is also referred to as an underground temple.

It is a class A river (specified waterways of special importance protected by the government) belonging to the Tone River system and is a ministerial management section (section outside the designated section) under direct control of the national government.
The Metropolitan Area Outer Underground Discharge Channel, which is located directly under the National Route 16 highway, has the ability to reduce flooding in the Naka River, Kuramatsu River, Ootoshi Furutone River, No.18 Channel, and the Komatsu River.

The Function of the Metropolitan Area Outer Underground Discharge Channel

Photo：The Metropolitan Area Outer Underground Discharge Channel

The Metropolitan Area Outer Underground Discharge Channel, located 22m underground, is 177m long, 78m wide, and 18m tall.
Each pillar weighs 500 tons, and 59 of them line the inside of the channel.
You can see the pillars lined up in the facility from 1:05 in the video.

The Metropolitan Area Outer Underground Discharge Channel consists of an "inflow facility" and a "vertical shaft," a "tunnel" that drains floods, a "pressure control water tank" that weakens the force of water and secures the flow, and a "drainage pump station" that discharges floods.
In the event of a flood, rainwater is stored in the Metropolitan Area Outer Underground Discharge Channel and then pumped out to the Edo River to prevent damage.
During Typhoon No. 19 in 2019, it helped to dramatically deter damage by filling with water to 90% of its maximum capacity.

Summary of the Metropolitan Area Outer Underground Discharge Channel of Saitama Prefecture

Photo：The Metropolitan Area Outer Underground Discharge Channel

The Metropolitan Area Outer Underground Discharge Channel is a comprehensive and lifelong learning facility, and you can tour the inside of the pressure-regulating water tank that is introduced in the video (reservations are required).
During the tour, you can see the operation room show at 0:37 in the video, and the first vertical shaft that you can see from 1:48 that guides the drainage from the river, so if you want to experience one of the safeguards protecting Saitama from mother nature, be sure to visit the facility.
If you want to tour the facility, be sure to stay on the lookout for the Showa Drainage Pump Station that can be seen from 0:21 in the video, in the underground exploration museum for the Metropolitan Area Outer Underground Discharge Channel, which is also called "Ryu Q Kan."

【Metropolitan Area Outer Underground Discharge Channel】
【Address】720 Kamikanasaki Kasukabe City, Saitama Prefecture
【Access】10 minutes by car or bus from Tobu Noda Line Minami-Sakurai Station

【Official Website】Metropolitan Area Outer Underground Discharge Channel
https://www.ktr.mlit.go.jp/edogawa//edogawa_index045.html

【Tripadvisor】Metropolitan Area Outer Underground Discharge Channel
https://www.tripadvisor.com/Attraction_Review-g1021410-d12864760-Reviews-The_Metropolitan_Area_Outer_Underground_Discharge_Channel-Kasukabe_Saitama_Pref.html