“Fool of a Took!”

Trees grow as deep as they are tall, and lots of cities follow the same principle. Sewers, electric and communications cables, serving as a city’s arteries usually run as deep as the skyscrapers are tall. Tokyo, one of the largest cities in the world, is certainly no exception. Tokyo’s underground infrastructure spans miles underground in every direction, including miles and miles of underground tunnels that stretch as far as 30 miles away. What exactly are those tunnels for?

Nothin’ But a G-Can Baby

The official name of these long, underground tunnels is the “Metropolitan Area Outer Underground Discharge Channel” (首都圏外郭放水路), but is more commonly called G-Cans. In writing this post, I wasn’t able to figure out why exactly the project was called G-Cans, but knowing Japan, I can only guess that it’s some sort of crazy Engrish amalgamation. My best guess so far is “government can,” a phrase of immense inspiration and little sense.

Edit: Commenter Chris mentioned that it probably stands for gesuikanaru (下水カナル), or drainage canal.

G-Cans itself is something of a modern engineering marvel. The idea behind the project is pretty straight forward: divert all of the rainfall from typhoons, other storms, and floods away from cities and towns around Tokyo and release it all into the Edo River, where water can’t damage homes and other buildings.

Yes, that’s a truck.

How It All Works

The way G-Cans does this is pretty complicated. It directs the water through a series of giant containment silos that are big enough to each hold their own space shuttle. Not that will ever happen, R.I.P. space shuttle program :(((

From the silos, the water works its way through a series of tunnels and finally up to the giant room with columns you see at the top of this post. From there, massive engines power out 200 cubic meters or 53,000 gallons of water per second into the Edo River.

If you’re still having trouble envisioning how G-Cans works, don’t worry. Just take a look at the comic about a dragon-turned-government-employee and an angry storm cloud that the Japanese government created to educate children about G-Cans. If the well-crafted dialogue and sophistication of an imaginary, anthropomorphized creature talking to a cloud about a civil works project doesn’t help you out, then I don’t know what will.

What Makes It Cool?

While the idea behind the project itself is pretty mundane (“Move water from Point A to Point B”), G-Cans is still an extremely impressive sight to behold. You can almost imagine the project’s massive columns and high ceilings as being part of the ruins of some ancient civilization or a level from Half-Life.

The massive scale of G-Cans might even make you wonder if there are things lurking about in the deepest parts of the expansive tunnel work. Ninja Turtles? Molemen? The newest AKB48 team? (If you believe the people at Land Rover, it’s impatient jerks with expensive cars.)

You can even visit G-Cans yourself if your Japanese is good enough for the all-Japanese guided tour. There’s information about the tour on the organization’s website, including important details like “Conditions of Participate.” You can see the tour’s English-language website here, or if you don’t think you can go to Japan and have the necessary Japanese vocabulary to understand what the tour guide is talking about, check out this YouTube video of somebody taking a tour:

[yframe url='http://www.youtube.com/watch?v=a3lUHB606U4']

If watching some anonymous Japanese tourist doesn’t suit your fancy, then maybe hip-hop mogul Pharrell Williams will do instead. Mr. Williams, in between producing sweet beats and rapping with the likes of Snoop Dogg, recently visited Japan in wake of the 3/11 disaster and filmed his visit. The result is the documentary “Tokyo Rising,” in which the Grammy-winning musician decided that visiting a flood control project would be a cool thing to do.

You can check out Pharrell visiting G-Cans in this video.

Are you an engineering nerd? Know what “G-Cans” means? Let me know in the comments.

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