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Japan To Build 250-Mile-Long, Four Storey-High Wall To Stop Tsunamis

Posted by samzenpus on from the no-wake-zone dept.

An anonymous reader points out this daunting construction plan in Japan. "Japanese authorities have unveiled plans to build a giant 250-mile long sea barrier to protect its coastline from devastating tsunamis. According to the proposals, the £4.6bn ($6.8bn) barrier would reach 12.5m high in some places – stretching taller than a four storey building. It would be made out of cement – and actually be composed of a chain of smaller sea walls to make construction easier. The plan comes four years after a huge tsunami ravaged Japan's north-eastern coast."

27 of 197 comments (clear)

  1. Most of Japan is very beautiful... by Rei · · Score: 4, Interesting

    .... but their beaches, usually not so much. So hopefully this won't be too much of an eyesore. Japan is usually pretty good about trying to fit human-made structures into the landscape; my friends and I had a running joke when we were there: "They have the prettiest drainage ditches here!" ;) That said, a 250-mile long, 4-story "anything", that's going to be hard to make look nice.

    I'm rather curious about what kind of concrete they're going to use. Japan has been a pioneer in the use of fiber-reinforced concrete, I wonder if they'll use that in lieu of steel that may need cathodic protection in such a high salt environment?

    --
    "99 dead duelists of Dios on the wall. 99 dead duelists of Dios! Take one's ring, pass it around..."
    1. Re:Most of Japan is very beautiful... by AmiMoJo · · Score: 3, Informative

      There are already a lot of these walls in Japan and they are not really ugly. They aren't walls like you would surround your house with, they have sloped sides. There is usually a path along the top and stops or slopes at intervals. They are grass covered, and sometimes lined with trees but usually kept clear. More like mounds than what most people think of as walls.

      --
      const int one = 65536; (Silvermoon, Texture.cs)
      SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
    2. Re:Most of Japan is very beautiful... by Whorhay · · Score: 2

      The OP is talking about using fiber instead of rebar. Steel rebar is a problem because it eventually will rust which damages the integrity of the wall.

    3. Re:Most of Japan is very beautiful... by nospam007 · · Score: 2

      "Most of Japan is very beautiful... but their beaches, usually not so much."

      Yea, all that whale and dolphin blood stinks to heaven.

    4. Re:Most of Japan is very beautiful... by ShanghaiBill · · Score: 2

      They're not using concrete; according to the blurb, they're using cement

      Using pure cement, without aggregate, makes no sense. This is almost certainly just a dumb journalist.

      But building the wall at all makes little sense. It takes centuries for the stress in the fault line to build up enough for a really big quake. They just had a HUGE 9.0 quake, so another is not due for a long, long time. Sediment records show they occur approximately every 300 years. This is just pandering to the construction companies that are big political donors to the LDP.

    5. Re:Most of Japan is very beautiful... by davester666 · · Score: 2

      Yeah, the Berlin Wall had a lot of nice murals on it.

      --
      Sleep your way to a whiter smile...date a dentist!
  2. Ugly Solution by Anonymous Coward · · Score: 4, Interesting

    A huge wall seems like an ugly and in-elegant solution. Building large mounds of forested areas would be much more attractive and useful (as a wildlife, tourist, and a tree resource). As a backup - build man made lakes at a higher altitude that can dump into the ocean in under 20 minutes and time the water dump to coincide with the tsunami. I would much rather be surrounded by trees and lakes than look at a big, ugly wall when I went to the beach.

    1. Re:Ugly Solution by Anonymous Coward · · Score: 2, Informative

      To continue, your suggestion of "mounds of forested areas"... sounds like you have no sense of what forces happen in the ocean. Even just to keep a developed beach, a lot of money gets spent moving the sand back to its original position. Sand normally moves along the shoreline, so as soon as one part is developed, sand from that region isn't moved downstream... so then at your beach, you put up groins to help maintain your sand, but then sand builds up on one side... basically, if you give a damn what your shoreline looks like, someone is spending money to maintain it, even if it looks "natural" to you. The artificial islands that you see in the news exist because people have more money than sense.

      A few years back, there was a local news story about a person that went along the beach, picking up stones that they saw, thinking that they washed up there and were ruining the beach... when really, the sand just got transported offshore like it does every year from the larger storm waves, and comes back from the more gentle waves in the spring. The rocks are supposed to be there, and always were.

      The engineers working on this problem, they know more than you. Debugging a few Java programs does not an ocean engineer make.

    2. Re:Ugly Solution by drinkypoo · · Score: 4, Interesting

      That the proposal is just bare concrete seems completely inexplicable to me; not only is concrete ugly as sin, it's also hugely unfriendly to the environment in terms of CO2 production.

      You're not familiar with Japan, are you? You may not be able to get a permit to cut down a tree in your yard, if you're lucky enough to have one, but they're perfectly happy to buy up every redwood tree they can convince someone to cut down on their behalf. They coat them in tar and sink them beneath the ocean. Mature redwoods are some of the world's most efficient fixers of CO2; a mature tree actually fixes more carbon than the equivalent mass of young trees, or the equivalent area coverage of same.

      Japan gives not one tenth of one fuck about environmental impact, so long as it doesn't affect them, just like everyone else. And they seem to be incapable of recognizing that the things they are doing are doing that, just like everyone else.

      --
      "You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
    3. Re:Ugly Solution by zippthorne · · Score: 2

      So.. they should learn from the dutch and build a series of walls?

      --
      Can you be Even More Awesome?!
    4. Re:Ugly Solution by aevan · · Score: 4, Funny

      *ahem*

      researched whales into extinction.

    5. Re:Ugly Solution by AmiMoJo · · Score: 2

      Some tress can't be removed because they have historic or particular aesthetic value. That sort of thing is common in many countries in Europe as well.

      On the other hand, after the war Japan planted a lot of trees to provide a source of cheap building material. Unfortunately they produce a lot of pollen that causes allergies, especially if not carefully managed. For that reason many are now being removed, and either replaced with less bothersome trees or the land used with something else.

      --
      const int one = 65536; (Silvermoon, Texture.cs)
      SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
    6. Re:Ugly Solution by Ol+Olsoc · · Score: 2

      I'm sure politicians, and not Engineers are deciding this.

      Absolutely. And when Politicians and their Excel enabled lackeys - the bean counters - get involved, you'll find thatThere will be studies and presentations to show now much money will be saved by making the wall X feet shorter.

      A very good example of this is the fencing systems along American interstate highways. Supposed to keep deer and other big animals away. Some one with more power than brains made the decision to save money, and made the fences shorter. Too bad the deer can jump over it. Rather than blocking them, it's just like an exercise programs for the ones that don't get disintegrated.

      Prudence demands that you use historical evidence of the highest Tsunami. There are gravel lines all over the coast that are physical evidence, Then you add in a safety factor. Then you build, without the bean counters telling you to lop off a few feet.

      But people haven't changed since the days when Fukushima was built, with a seawall that was lower than expected Tsunami waves. I was shocked when my research showed that the facility being swamped was not only possible, but simply was going to happen. The evidence both in the historical and geological record said so.

      BTW - I'd suggest that they might think about release gates to let the breachwater back out after the wall is topped because of cost saving measures.

      --
      The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
    7. Re:Ugly Solution by spauldo · · Score: 2

      It does, actually, it just requires the right geography.

      Here's one that hit Alaska back in the 50s.

      Imagine what would happen if an earthquake in the north Atlantic caused a tsunami in Norway. You'd get insanely high waves in the fjords.

      --
      Those who can't do, teach. Those who can't teach either, do tech support.
  3. Tsunami watch by The+Evil+Atheist · · Score: 4, Funny

    We are the tsunami watchers on the wall. Waves gather, and the soiling of my pants begin.

    --
    Those who do not learn from commit history are doomed to regress it.
  4. Will that be enough? by hcs_$reboot · · Score: 5, Interesting

    In 2010 I visited a small town in Iwate where a high tsunami wall had been built 40 years before. In March 2011, the town has been completely devastated by the tsunami. Will the new wall be high and solid enough? That's an interesting question, but we won't probably know the answer (fortunately) before another few hundred years.

    --
    Slashdot, fix the reply notifications... You won't get away with it...
  5. Yeah! by nospam007 · · Score: 4, Funny

    Good-bye 12.49 Meter tsunamis, welcome 13 meter tsunamis.

  6. Does Moore's law apply to Tsunamis? by Quick+Reply · · Score: 3, Insightful

    It doesn't matter how big you engineer for, sooner or later something big enough will come along and topple everything. Containing high water levels in nature has been tried many times before and they always fail sooner or later.

    1. Re:Does Moore's law apply to Tsunamis? by Neil+Boekend · · Score: 5, Insightful

      Water often looses. See the Netherlands. In fact: hire the Dutch to design your wall.

      --
      Well, I might have a way, but it only works on a semi spherical planet in a vacuum.
  7. You'd never get it by the NIMBYs here by msobkow · · Score: 2

    If the NIMBYs have a problem with windmills "destroying the view", imagine how they'd react to this plan if it were enacted here in North America.

    --
    I do not fail; I succeed at finding out what does not work.
  8. It won't work... by Anonymous Coward · · Score: 3, Insightful

    The problem is the wall itself. There will be earthquakes to first crack it.

    And "water always wins", as the Doctor says.

  9. Didn't help with Kaijus... by alexjplant · · Score: 5, Funny

    Have we learned nothing from history? We need giant wave-breaking robots piloted by a pair of unlikely heroes to stop the tsunamis. Preferably with giant extendable swords to cut the breakers down to size.

  10. Anti-Kaiju wall by gijoel · · Score: 5, Funny

    It also doubles as an anti-Kaiju wall. Just the thing to keep out those pesky monsters like Mothra, Gamera, and Godzilla*

    * May not actually keep Godzilla out.

  11. Or... by Overzeetop · · Score: 3, Informative

    You could not build any critical infrastructure within a set distance from the coast, and no habitable buildings within a second less restrictive distance. This is basic risk mitigation. You don't build critical facilities on a fault line, you shouldn't build one in the direct path of a (potential) tsunami. Go look at the USGS website, or any of a number of wind zone maps. All this stuff has data and is plotted out for the US - all you have to do is set your risk factor (50 years for hurricane/snow, 500 for earthquake in the US) and note your exceptions.

    --
    Is it just my observation, or are there way too many stupid people in the world?
    1. Re:Or... by HideyoshiJP · · Score: 2

      Sadly, Japan has none of that luxury. I mean, all the land is either an agricultural area, developed area, or mountain (which sometimes is also agricultural or developed. Then there's the whole volcanic island chain full of faults thing. Even if you put everything on the back side of the mountains, they get such heavy snowfall you'd have trouble keeping things running through the winter.

  12. Australia by Chuq · · Score: 5, Funny

    South-east Australia already has a similar barrier. We call it "New Zealand".

    --
    - Chuq
  13. Is anyone else reminded of King Canute? by JThaddeus · · Score: 3, Interesting

    "But the sullen ocean answered with a louder, deeper roar,
    And the rapid waves drew nearer, falling sounding on the shore;"
    --William Thackeray King Canute

    --
    "Love is a familiar; Love is a devil: there is no evil angel but Love." --William Shakespeare ('Love's Labors Lost')