Other times, you wonderful readers/friends will suggest something to me or ask a question that gets my so-called juices flowing and I just have to research it to sate my curiouser and curiouser curiosity.
And then other times my friend Michael will pop over to my work desk and wonder if I am working on work or the blog (only at lunch time!), and then curiously mention that he has a reproduction of a Tokyo map that shows the island he used to live on in that city.
Michael spent five years in Japan teaching English but did not do so on the JET Programme, proving that is not the only way to fly. He was there around the same time I was there in the early 1990s, and even though we have both visited Tokyo Disneyland a few times, but we never met because it's not really that small a world, after all.
Anyhow… Island? What island? I'm not all that familiar with the layout of Tokyo. I lived in the rice fields some 200 kilometers (120 miles) away, and when I did go into the city, I did so to go dancing with some babe, visiting a museum or shopping for electronics and English-written books. Not much else yanked my crank as I'm from a big city and why be turned on by another big city?
He mentioned that he lived in a part of Tokyo known as Kachidoki - saying it translates to 'shout of freedom', and that if I cared to look at the original Godzilla movie from 1954, I can see the King of the Monsters kicking over the Kachidoki bridge. He also mentioned that the Kachidoki area was part of some reclaimed land done just before the 20th century began.
And then there was something about Japanese pancakes.
Cool. Even if I was interested in learning more when he mentioned Godzilla, he had me at 'pancakes'.
Reclaimed land? I know something about that. Not only is Centennial Park's hill (directly beside where I coach a kid's soccer team) made up of garbage, but most of the city of Toronto's waterfront area is also made up of reclaimed land… I wrote a major history essay on that back in university… pssst… it's why Front Street in Toronto is no longer at the front… everything below it is made up of reclaimed land.
And so, it came as no real surprise that Japan would have built up itself using reclaimed land, too.
I was a bit surprised, because I did wonder if reclaimed land was as strong as regular land - when it comes to earthquakes… but… well, let's find out.
Umetatechi is the Japanese word for 'reclaimed land' and approximately 0.5% of Japan's land area is actually made up from reclaimed land.
It doesn't sound like a lot at first glance, but it is upon second glance. That's me suggesting you take more than one glance.
While most of Japan's umetatechi was actual undertaken AFTER WWII (1945), with about 80% of Japan's tidal flatlands reclaimed, Japan first began the task of performing land reclamation as early as the 12th century.
Why does anyone reclaim land from the waters? To have more property.
Reclaimed land is made up of a whole lot of things, from sand from dredging, from construction areas, rocks, waste materials, and garbage.
It can even be made up of material waste taken from areas exposed to radiation after the March 2011 Tohoku earthquake and nuclear radioactive fallout problem.
Yup… some places in Japan could be built up from radioactive materials.
Ooh-ah. Don't panic. Have you ever been to Hiroshima or Nagasaki? I have. Somehow after the atomic bomb(s) clean-up, no one's face has fallen off.
Tokyo has been taking in rubble and waste products from areas hit hard by the March 11, 2011 earthquake, tsunami and Fukushima radiation fallout.
The material is all tested, of course, for radiation contamination, and as long as it's under the dictated radiation levels of 8,000 becquerel per kilogram, it will be further processed and used to create landfill in Tokyo Bay for more land reclamation.
The soil (et al) is measured for Cesium radioactive contamination before it leaves the Tohoku region and again when it arrives at the Tokyo processing center.
The soil is to be used to create a new island south of Odaiba in the Chuo Breakwater Iaslan area of Tokyo Bay, with it expecting to have received some 500,000 tons of material from Iwate-ken and Miyagi-ken through the end of 2013.
And yet, proving once again that people are simply misinformed in every country, Japanese citizens are protesting the use of this material as landfill.
I'd be more concerned that someone's unclaimed body or articles belonging to someone who died in the 2011 triple disasters might become part of the landfill, and then you'd have one of those angry ghosts with the long hair covering the front of their face oozing water from its mouth walk out towards you in the dead of night when it is always dead. In the night. Dead. Brrrrr.
Anyhow, I wondered about how safe it was to construct anything on land reclaimed via filling in the water with dirt.
Well, it's been over 100 years and Toronto hasn't had any problems with buildings collapsing with the pain and the horror and the flaven. Then again, we might get a 4-point-something earthquake once every few years, and nothing stronger.
Japan… well, as of July 4, 2014 at noon EST, there have been 3,073 earthquakes to hit Japan since Friday, March 11, 2011 at 1:54AM. I have my ways.
Okay, okay… click HERE for a very cool Japan Earthquake Map.
Anyhow… apparently there is a bit of concern that land made up of reclaimed bits can indeed be at greater risk of liquefaction.
It is exactly what it sounds like. Thanks to the shaking or heaving of the ground during an earthquake, soil can lose its strength and stiffness and start behaving like a liquid making it unlikely to be able to support buildings et al above it.
Can it happen in Japan? Liquefaction has occurred plenty of times in Japan's history.
There was some liquefaction during the March 2011 earthquake, but not a tremendous amount - but with so many areas left flooded by the subsequent tsunami, perhaps that possibility hasn't been fully examined yet.
However, because liquefaction is a concern when building - not just on newly reclaimed land - but even if the area may have been reclaimed centuries ago - before new construction can begin atop it, the strength of the ground is checked. Japan does follow some pretty rigid earthquake resistance standards and testing of ground strength prior to any construction.
Should you be worried?
Well… not if you are going to be in a huge industrial or commercial block, because Japan will perform drilling to check out the overall land strength…
But maybe you should be more concerned if you are going to be in a residential area… because drilling tests cost s a lot of money. So a cheaper test - the Swedish Weight Sounding Test - is used.
You can view a YouTube video on just what this is, below:
I am unsure what happens if you weigh more than 100 kilograms? Fortunately I am under that now, so I shouldn't sink into the ground anymore.
After the March 11, 2011 Tohoku earthquake, we should note that there were actually over 75 strong to medium earthquakes and tremors over a 24-hour period.
Now, there were some reclaimed land areas that seemed to take considerable damage after the quake, including Urayasu-shi in Chiba-ken, just north of Tokyo.
Having been shaken, many people in Japan are stirred to action, wanting now to make sure any home they move into, is on solid (and safe) ground.
That's interesting considering that they should always have been checking to ensure they are on safe ground.
Surprisingly or not, apartment buildings and other high-rises on reclaimed lands did NOT suffer any damage—probably because of all of the thorough testing they performed before construction.
However, because we are just talking about pipes for water and gas, they did get torn apart in the earthquake. Hey- something's gotta give.
The first man-made island in Japan was Kyogashima in Kobe. The island was built by Kyomori Tairano (surname first) in 1173AD.
Then, as now, Kobe is a major port city of Japan, so the land reclamation was used to better facilitate sea trade.
Since then, the island of Kyogashima has become absorbed by even more land reclamation in and around Kobe. It is suspected that this original isle of Kyogashima is currently part of the are between Wadamisaki Station and the Hanshin Expressway No. 3 Kobe Route. Maybe.
Other big reclamation jobs include the Hibiya Inlet which began in 1592 in Tokyo.Before this, ships could sail all the way up to the Imperial Castle. With the land filled, it was given to daimyo (feudal lords).
Another biggie was Deijima, a man-made island constructed in 1634 to deal with trade during the Isolation era (sakoku). The Dutch and Portuguese traders could stay there on the isle and commence trade with Japan - but no one else. It is currently a Japanese historical site, but it is hardly an island anymore as land has been reclaimed north of it to make it a part of Nagasaki.
After the incursions by the Americans and Commodore Matthew Perry and his so-called 'black ships in 1853 (the U.S. wanted Japan to open up its doors to international trade with the U.S. - which would help legitimize its claims as being a world leader) Japan's shogunate in 1853 constructed six island forts around Tokyo Bay, to help protect it from attacks by ship - specifically American ships.
These six man-made islands were to have included 11 canon batteries, but only five were completed.
One other area that I'm going to touch upon, is Tsukishima (月島), a man-made island completed in Tokyo in 1892 - this is where my friend Michael (mentioned as the brains behind this blog idea) used to live. The dirt was moved to form the island from a freshly dredged shipping channel created in Tokyo Bay to handle all that sea traffic from American and European traders. A second part of the island (expansion) known as Kachidoki (勝どき / かちどき) is known as “Shout of Victory“, and was completed in 1894.
I'm guessing those canons were not required to keep out all that American economics.
As you can see, Tsukishima is written with the Japanese kanji 月島 - which means Moon Island. But, pronouncing it exactly the same way, but using different Kanji, Tsukishima was originally called the less-romantic "constructed island."
And… because my pal Michael mentioned it, and Wikipedia backs him up, Tsukishima is well know for its monjayaki pancake, which is made with a dough more liquify (see liquefaction above) than the perhaps better known far less runny okonomiyaki. Monjayaki is supposed to have the consistency of a pool of melted cheese. That photo at the top is a pan of monjayaki.
Mmmmm. I'll put in the claim that I would eat it, but I sure wouldn't construct a building on it - especially considering its shaped like a little man-made island.
Okay… that was a stretch to make the joke.