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Japan Earth

Japan To Build 250-Mile-Long, Four Storey-High Wall To Stop Tsunamis 197

Posted by samzenpus 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."
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Japan To Build 250-Mile-Long, Four Storey-High Wall To Stop Tsunamis More

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

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  • Most of Japan is very beautiful... (Score:5, Interesting)

    by Rei ( 128717 ) on Thursday March 26, 2015 @05:39AM (#49342927) Homepage

    .... 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?

    • Re:Most of Japan is very beautiful... (Score:4, Informative)

      by AmiMoJo ( 196126 ) * on Thursday March 26, 2015 @08:46AM (#49343671) Homepage Journal

      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.

      • Re: (Score:2)

        by jrumney ( 197329 )
        Often river embankments are grassy mounds, but they're more for seasonal flood control than tsunamis. The tsunami walls I've seen along beaches are very much concrete walls, and while they do have a roadway along the top and sloped sides with steps at intervals and the occaisional roadway leading up to them, they are anything but attractive.

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

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

    • " That said, a 250-mile long, 4-story "anything", that's going to be hard to make look nice."

      As long as you can see it from the moon, it will be a tourist magnet.

    • kinda like any engineering project, I guess... pick the maximum incredible external threat, and design resistance to... uh, wait, the budget got cut HOW MUCH? OK, well, guys, let's pick the maximum credible external threat we can protect against 80% of the time for under $7 billion. make it modular so we can truck 'em in. seaming with tape is OK if we have to.

    • Artificial mangrove swamp?

  • Ugly Solution (Score:4, Interesting)

    by Anonymous Coward on Thursday March 26, 2015 @05:40AM (#49342931)

    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.

    • Re: (Score:2)

      by Zocalo ( 252965 )
      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. Maybe the concrete (and presumably rebar) is needed for structural integrity but a more natural solution based on earthworks, possibly with a re-inforced core of rock/rubble, sounds like it would be less of a blot on the landscape and thus more acceptable to those who have to see it.

      Your idea of artificial lakes - perhap

      • Re:Ugly Solution (Score:5, Interesting)

        by drinkypoo ( 153816 ) <drink@hyperlogos.org> on Thursday March 26, 2015 @06:58AM (#49343185) Homepage Journal

        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.

        • Re: (Score:3)

          by AmiMoJo ( 196126 ) *

          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.

      • Re: (Score:2)

        by khallow ( 566160 )

        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.

        I don't buy your claim of "hugely". The problem here is that while it's a substantial pile of concrete and while that concrete will generate a lot of CO2 as it solidifies, there is a vast amount of atmosphere. It's just not significant even if you do buy fully into catastrophic AGW.

        Now, consider also the pollution from an unprotected coastline getting hit by a tsunami. Even if you ignore the various chemicals and debris washed into the ocean by the tsunami, there is a considerable amount of CO2 generated

        • Re: (Score:2)

          by Zocalo ( 252965 )

          I don't buy your claim of "hugely". The problem here is that while it's a substantial pile of concrete and while that concrete will generate a lot of CO2 as it solidifies, there is a vast amount of atmosphere. It's just not significant even if you do buy fully into catastrophic AGW.

          It's not just the *use*, it's also the production of the concrete itself which tends to get lumped in with the end product in environmental impact calculations. Production of concrete is responsible for approximately 5% of ALL

          • Re: (Score:2)

            by spauldo ( 118058 )

            The concrete used to create this wall is a drop in the bucket compared to the concrete used for making and maintaining roads.

            Yeah, it's a big wall, but think on this: in the US, the concrete that makes up the interstate system is at least 11" thick. That's not counting any asphalt layer on top. Each lane is 10' wide. It's 47,714 miles long (as of 2012, according to wikipedia). Not counting shoulders, exits, bridges, etc. and assuming (incorrectly) that the interstate system is four-lane all the way, tha

          • Re: (Score:2)

            by khallow ( 566160 )

            It's not just the *use*, it's also the production of the concrete itself which tends to get lumped in with the end product in environmental impact calculations.

            I know. That's why I posted. It's just not that much CO2 being produced by that much concrete.

            Production of concrete is responsible for approximately 5% of ALL mankind's CO2 emissions of which about half comes from the chemical process itself and almost as much from the fuel burnt to provide power for process, with the bulk of the contribution coming from the cement use which produces approx 850-900kg of CO2 per 1000kg of cement.

            Notice that you could offset about half of that emissions just by putting out all coal fires. Concrete is generally a very high value product for the amount of carbon dioxide produced and this case appears no different. I don't see the point of the complaint.

    • A huge wall seems like an ugly and in-elegant solution.

      Don't worry. Godzilla will just knock it down anyway.

    • Not only inelegant, but dangerous...to a non-Japanese country.

      If the entirety of Japan can rebuff a giant wave, then that wave must slosh back in the other direction (instead of being dissipated by land).

      So, who is responsible for such "bounce" waves?

    • 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.

      If you watched video of the 2011 tsunami, you've seen that it isn't a singular wave which comes ashore and retreats back (there are such tsunamis, usually caused by loca

  • Tsunami watch (Score:5, Funny)

    by The Evil Atheist ( 2484676 ) on Thursday March 26, 2015 @05:41AM (#49342933)
    We are the tsunami watchers on the wall. Waves gather, and the soiling of my pants begin.

  • Will that be enough? (Score:5, Interesting)

    by hcs_$reboot ( 1536101 ) on Thursday March 26, 2015 @05:42AM (#49342941)
    In 2010 I visited a small town in Iwate where a high tsunami wall [slidesharecdn.com] had been built 40 years before. In March 2011, the town has been completely devastated [s-nbcnews.com] 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.

    • Re: (Score:2)

      by Dunbal ( 464142 ) *
      No and no. This is a "feel good" project so that politicians can convince people they are doing something effective while not actually addressing the problem at all. In the meantime I'm sure that the politician's cousin/uncle/brother-in-law who surprisingly "won" the bid for construction is very happy. Politics as usual.

      • the politician's cousin/uncle/brother-in-law who surprisingly "won" the bid for construction is very happy. Politics as usual.

        Indeed, that's sad, and nobody in Japan will raise that problem high enough that it becomes a concern for everyone.

  • Yeah! (Score:5, Funny)

    by nospam007 ( 722110 ) * on Thursday March 26, 2015 @05:47AM (#49342949)

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

    • Well you have only 0.51 meter of the sea coming inside.

      • Re: (Score:2)

        by Dunbal ( 464142 ) *
        No. You've never seen what happens to a wave when it hits a wall? All that energy has to go somewhere and if it can't move laterally it will move vertically. How's this [telegraph.co.uk] for 0.51 meters? That's just a normal wave, not one with a wavelength of > 1 km like a tsunami.

        • Re: (Score:2)

          by aevan ( 903814 )
          When that water falls from its vertical movement, how much horizontal movement is there compared to the initial wave? i.e. is it still going to devastate inland nearly as far?

          • Re: (Score:2)

            by Dunbal ( 464142 ) *
            You're thinking of a wave not a tsunami. Think about rapids in a river, and the standing waves you get over those rocks that are much higher than the surrounding water. A tsunami has a waveLENGTH of several km at least. That is a LOT of volume of water that is going to move up and over the wall.

    • Re: (Score:2)

      by dcw3 ( 649211 )

      My wife insists that size doesn't matter.

  • Does Moore's law apply to Tsunamis? (Score:4, Insightful)

    by Quick Reply ( 688867 ) on Thursday March 26, 2015 @05:52AM (#49342965) Journal

    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.

    • Re:Does Moore's law apply to Tsunamis? (Score:5, Insightful)

      by Neil Boekend ( 1854906 ) on Thursday March 26, 2015 @06:53AM (#49343167)

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

      • Yeah, the Dutch are known for being very good water tighteners.

      • Re: (Score:2)

        by radja ( 58949 )

        I expect Japan will hire dutch firms. Japan and the Netherlands have a long history together (including a 200+ year monopoly on trade)

      • Comment removed based on user account deletion
        • New Orleans and much of the surrounding area is sinking at about one inch a year. There is no permanent fix to this problem.

          • There are no permanent fixes in our world. Things wear and need maintenance. One inch a year should be taken into account with normal maintenance but that doesn't mean it'll cost extra.

          • Re: (Score:2)

            by Lotana ( 842533 )

            Why was the city even established in such a terrible place? Didn't the surveyors notice the elevation was bellow sea level?

      • Consider also the case of the town of Fudai, whose mayor in the 1970s, insisted on building a 15.5 meter (51 foot) seawall to protect against tsunamis. This was much higher than most people thought was necessary at the time, but it saved the town from the March 2011 tsunami.

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

        No, hire Vogons to read poetry to it.

        This causes the Tsunami to turn immediately and hurl itself in the other direction.

    • No, they don't double every year or two. If they did, they'd already be past the moon. They do follow a scale-free distribution, whereas intuition probably makes you think it's a bell-curve. While they're preparing for a tsunami as big as the last one, they forget that before the last big one they were preparing for one as big as the one before it.

    • 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.

      So is it a bad idea to be protected against 95% of all tsunami, instead of 75%?

  • You'd never get it by the NIMBYs here (Score:3)

    by msobkow ( 48369 ) on Thursday March 26, 2015 @06:00AM (#49342991) Homepage Journal

    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.

  • May as well build an anti gravity device and get done with it ;-)

  • It won't work... (Score:3, Insightful)

    by Anonymous Coward on Thursday March 26, 2015 @06:20AM (#49343049)

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

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

  • Comment removed (Score:5, Funny)

    by account_deleted ( 4530225 ) on Thursday March 26, 2015 @06:32AM (#49343085)
    Comment removed based on user account deletion

    • An extendable, super powerful sword that they mysteriously forgot about until they *really* needed it, as opposed to simply chopping up all the easier monsters with it.

      • No, no, they didn't forget about it - the sword is powered by the desperation of the pilots, so it's only worth using when things get really bad.

    • Exactly! Came here to say this. Perhaps the giant robot program could be led by Japan's agriculture ministry.

  • Anti-Kaiju wall (Score:5, Funny)

    by gijoel ( 628142 ) on Thursday March 26, 2015 @06:37AM (#49343097)
    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.
  • the Kaijus?

  • Or... (Score:4, Informative)

    by Overzeetop ( 214511 ) on Thursday March 26, 2015 @06:48AM (#49343139) Journal

    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.

    • 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.

    • Have you looked at a picture of Japan lately? The country is in the shape of a string bean. Imagine telling US citizens that 20% of the best land is now off limits, good luck with that.

      • It's not really the "best" land so much as the "most desirable". We actually tend to like to build on land that we would be better off using to grow food, and farmland would be the kind of thing you could do with land that could be threatened by a tsunami.

    • Re: (Score:2)

      by dcw3 ( 649211 )

      You don't build critical facilities on a fault line

      Really? How many critical facilities already exist on fault lines...being on the fault line doesn't matter. The earthquake that damaged the Washington monument had an epicenter in Mineral, Va roughly 85 miles away. You certainly could build facilities in extremely low risk areas, but then you have to find people with the expertise and willingness to work that them. Clearly from the USGH hazard map, we shouldn't put anything on the entire west coast, Hawaii, or the Alaskan coast.

  • Well at least people will *feel* safe.

  • Australia (Score:5, Funny)

    by Chuq ( 8564 ) on Thursday March 26, 2015 @07:06AM (#49343221) Journal

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

  • Surely you mean concrete.

    Cement is only one ingredient in concrete.

  • Is anyone else reminded of King Canute? (Score:4, Interesting)

    by JThaddeus ( 531998 ) on Thursday March 26, 2015 @07:23AM (#49343299)
    "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 [allpoetry.com]

  • Since I'm not an expert in fluid mechanics, my first question would be, not that a wall would be totally unhelpful, but would it be far more useful, practical and conservative to find a way to break the momentum of the water hitting the land?

    I saw artificial reefs suggested above, but are there any other methods of doing this?

    I don't know, I mean Pacific Rim jokes aside (which I'm very glad to see a number of you were on top of as I loved that movie), but I think a wall seems a short-sighted an impractical

  • They should outsource the wall design and construction to the French. They have experience building walls/defense. [wikipedia.org]

    Then they outsource the testing for effectiveness to the Germans. [wikipedia.org]

  • Constructing a wall to withstand a tsunami at the very least will be challenging and may in fact be impossible. And a 40 ft. wall may be as useless as teats on a bull. What would a fifty foot wave do to a 40 ft. tall wall? It is difficult enough to build a dam that will hold calm water but the speed and weight of water in a Tsunami is a whole different kettle of fish. Maybe tsunamis could be called home delivery for sushi.

  • Americans could build Berlinesque walls on the norther border at that price/hour, in addition to another to the south and along the eastern seaboard and the Pacific coast.

  • If you can stop a jaeger, you can stop a tsunami.

  • First I think they need to work on having enough people in their country to make such a wall worth it... The way their population is declining, pretty soon even if a tsunami hits, no one will be left in the country to notice it.
  • They're meaning Godzilla.

  • Exactly who are these 'authorities'? Where are the 'plans'? Who approved the money for this project and why do the citizens have no say in it? Later the word 'proposals' is used; so is it a plan or a proposal?

    This is very poor journalism. Not a single authority is identified. There are references to two critics of the project who have no authority and their opinion doesn't matter. There is no substance to this story at all, no citations, no evidence that it is not just in the reporter's imagination.

    & ce

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