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I took a trip to this place when I was in Tokyo last spring; here are my pictures for the curious:
https://memorymulch.net/journal/2018/11/18/maoudc
It cost about 80 bucks all told and was a bit of an ordeal to organize (you need a fluent Japanese speaker), but was definitely an experience. It was a little disappointing in how limited our tour was. I get the sense that they've narrowed down the area you can wander since opening. Still, I've explored storm drains in the US quite a bit and this was a whole different level.
I went here in 2006.
Didn't need a translator or Japanese (but booking the appointment in the site pre-google translate was fun..)
We caught a train out, and walked the remaining 2km to the facility.
Great to see you can get onto the floor now !
http://ninjito.com/2006-07-04 http://ninjito.com/images/2006-09-22/qx-pano-18.jpg
Wikipedia says this place can be visited for free. Is the part you paid basically for transportation and translator / tour guide?
https://en.wikipedia.org/wiki/Metropolitan_Area_Outer_Underg...
The tour is free, but yeah, I had to pay transportation for myself and the guide (who I arranged online after some googling). The actual site is fairly far from central Tokyo, so it's about a 20-30 dollar train fare.
The guide himself was free, a nice older gentleman who used to be some sort of government liason. He insisted on taking a taxi for the 2 miles from the train station to the tour though, which was pricey. But I didn't have much of a choice (despite a whole face-saving false choice he offered of walking vs taxi that was deeply emblematic of a certain strain of Japanese cultural weirdness).
What happens if you choose to walk?
He offered to walk or take a taxi, but when I said I was fine with walking he just kept repeating the same the question with increasing emphasis until I agreed to the taxi.
Your pictures are stunning. The entire facility has quite a sci-fi aspect to it. Did you actually run into any hornets? :)
Thanks! Didn't see any scary hornets sadly. The whole structure is totally sci-fi, even inspiring a level in Mirror's Edge.
You might also enjoy some of my other drain exploration shots from stateside:
> The entire facility has quite a sci-fi aspect to it.
Which is likely why it's a common backdrop for many a Tokusatsu shows[0]. Every season of Kamen Rider[1] -- and likely Super Sentai[2] as well; I'm not sure since that's too juvenile for my taste -- is all but guaranteed to have at least one episode filmed there.
[0] https://en.wikipedia.org/wiki/Tokusatsu
Either Scifi or Fantasy as it also looks like Peter Jackson's Moria. http://lotr.wikia.com/wiki/Khazad-d%C3%BBm
What's cool to me is not only the planning and engineering involved in creating these sorts of responses, but ability to accumulate the funds, the political will, and the discipline to see it all go through start to finish.
Read about Chicago’s Tunnel and Reservoir plan.
It’s a 60 year underground water infrastructure plan that’s been miraculously more or less on schedule and budget.
The Chicago system is about 2 orders of magnitude larger (someone might want to check my pre-coffee morning math), but a very big distinction is that Chicago stores the overflow water in outdoor, open-air reservoirs, not underground storage tanks.
I agree that it is rather impressive for a long-running American construction project to be on-time and on-budget, but keep in mind that most of the project has been tunneling through very consistent bedrock with nothing in the way. Also, the McCook Reservoir mentioned in the wikipedia article as 13x10^9 liters is a former limestone quarry that they purchased and then connected to the system. The wikipedia article says it will be expanded to 38x10^9 liters by 2029. That's true... but what is really going on is that all they've done is sign a contract to buy the quarry on the other side of the highway once the stone company is done with it, perhaps around 2026 or so. Only then will they do any construction to connect it to the system. Don't get me wrong, it's a very smart move. But it's not an 11-year long project for which they have to maintain a schedule and budget.
This is quite magnificent, some pictures here: https://ja.wikipedia.org/wiki/首都圏外郭放水路
wow, those pictures bring to mind the film depiction of the mines of moria in terms of scale and regularity
It's big, but I haven't seen any information about how the capacity of the system compares to the capacity of the rivers feeding into it to generate water. Would the system survive a Harvey-type event? Or is it meant to deal more with seasonal fluctuations to prevent runoff causing flooding? 100 tons per second doesn't seem like a lot to me, compared to runoff that can be generated during spring thunderstorms. It's impressive and no doubt Tokyo will benefit from the infrastructure, but really the main chamber does not look much larger than a dig for a large skyscraper.
In addition to the main chamber there are several pits that also store lots of water. Here's a photo I took on the tour that might show it better: https://static1.squarespace.com/static/5265796de4b0bacb22141...
Unfortunately I don't remember the tour specifics well enough to confirm the exact use case of the system.
From what I remember (and similar to other designs), the pits take the brunt of the flash flooding, before releasing into the chamber. The reservoir can hold the water for as long as required before dispatching it.
In the past few years there have been some large storms that missed Tokyo by a fairly small distance. The people who operate this system say that it would have been over capacity if those storms had hit Tokyo directly.
It's an impressive system but there are definitely still storms large enough to overwhelm it. But, combined with the other flood defenses in the area, it has made flooding less common in all normal weather scenarios, which is a big win compared to the situation before it was built.
The article talks about Tokyo being designed to handle 5 cm/hr of rain. That's extreme but not record breaking.
The rate given for the Edo Discharge Channel pumps in the article is 200 tons per second. At 5cm/hr, that's enough to drain a region 150km x 100 km, or the whole Tokyo metropolitan area.
There are other drains (like the Edo River itself) and other sources of rainfall, but based on that calculation 200 tons per second is a huge contributor to draining even a megacity.
Helsinki doesn't need flood protection, but we have a large (~25000 cubic meters) underground lake right in the center of the city for heat management: https://gizmodo.com/helsinki-built-an-underground-lake-to-co...
The local energy company is also converting some artificial caves, originally dug for oil storage, to similar use: https://www.helen.fi/en/news/2018/Gigantic-cavern-heat-stora....
Pretty awesome!
Reminds me of the cisterns underneath Istanbul (Constantinopolis), built by the romans.
There's a few things similar in Paris as well.
Most dense cities with little natural run off have them.
http://ninjito.com/2009-07-19
I love this level on Mirrors Edge
Came here to post this. Now I know where they got their inspiration! Though, ironically enough, I always got the vibe that that city from the first game was more like Singapore.
Now that’s what you call a GeoFront.
Any pictures of it flooded?
I searched and could only find pictures of it empty.
The ones we visited in Paris have 50cm thick solid steel doors and submarine hatch style wheels to wind them shut.
I would anticipate that even just the air pressure that is expelled during a surge is probably enough to cause serious damage to people.
On the scale of G-cans, it's hard to know if it would be more dangerous or less dangerous..
It's probably not safe for people when flooded; it's unlikely to be a static pond, but a cascading torrent.
... but yeah, now I want to see pictures of it in use :D
Last week we tried to book a ticket for a visit next month. (They have a strict schedule). Unfortunately seems tours suspended until March 2019.