Japan's Great Wall: Can It Stop A Tsunami? | Foreign Correspondent

a decade ago a massive tsunami slammed into japan wiping out everything in its wake killing thousands of i was based in japan as the abc correspondent when the tsunami hit the scale of suffering and destruction was truly devastating in its aftermath the government pledged to build massive sea walls to protect communities from future tsunamis 10 years on almost 400 kilometers of walls have been built but many say the walls designed to protect their communities actually put them at greater danger the critics say the great wall of japan has sliced the coastline cut communities off from their livelihoods and destroyed their culture many believe the billions spent could have been better used on evacuation plans and moving more towns to higher ground the government insists the wall does slow a tsunami's advance and increase evacuation times saving lives foreign correspondent investigates whether the great wall of japan is a solution or an expensive failure [Music] school students are visiting the coastal town of taro to learn about the 2011 [Music] tsunami [Music] [Music] after two devastating tsunamis in 1896 and 1933 tarot thought it was finally protected with this 10 meter high sea wall this x-shaped double levee has been held up as a model since its construction in the late 1950s technology all that changed on the 11th of march 2011. a tsunami resulting from a magnitude 9 earthquake killed 18 and a half thousand people and wiped out 560 square kilometers of land all along the northeastern coast of japan waves reaching 15 meters high swept away everything in their path vehicles homes people and the sea walls meant to protect them [Music] the failure of the old sea walls could have stopped the japanese building more but the opposite has happened japan is building new ones higher wider and longer [Music] it's a massive project 400 kilometers of sea walls with an average height of 13 meters at a cost of 17 billion dollars [Music] university says it's one of the biggest construction projects japan has ever undertaken or foreign [Music] most of the construction will be finished later this year the 400 kilometer continuous wall will close off every river along the splintered northeast coast of japan [Music] but the mega project has caused controversy and raised serious questions how much can we protect ourselves from natural disasters and can walls really save lives [Music] south of taro construction workers are starting their day the first task for the men is to consolidate the ground invaded by seawater with reinforced concrete piles before erecting the new barriers [Music] supported by foundation some 25 meters deep a 14 meter high seawall forms the front line backed by a 40 meter wide bank of earth covered with concrete slabs this levee will stretch for two and a half kilometers along norders beach to help his hometown rise up again from the devastation caused by the tsunami for him the new sea wall will be the best protection against future tsunamis [Music] the project also includes floodgates which are left open to allow rivers to flow into the sea they're only closed in the event of a tsunami foreign at the prestigious wasser university in tokyo researchers are still learning lessons from march the 11th twenty eleven three two one again and again this simulator reproduces a tsunami wave and the way it spreads and crashes into sea walls levees and buildings modelling their waves on those of the 2011 tsunami with an average of 15 meters and 40 meters at their highest the scientists found that no matter how high the sea walls are not all tsunamis could be stopped we made a very big discussion what will be the appropriate height of break waters and also the tsunami barriers and our final conclusion is that if the tsunami height is too high it is very expensive to protect perfectly and reflect waters so we prepare for the tsunami for once for 100 years if the tsunami height is more than that the we recommend the residents to evacuate from the judicial area before tsunami arrivals since the sea walls can't stop every wave they're being built to stay upright and in place if they are submerged but can they dilute the destructive power of a tsunami and make the residents behind the wall safer 440 kilometers north of tokyo in kamishi city kazanori yamamoto has some of the answers in the master work he designed [Music] at the entrance to kamiyashi bay the six metre high two kilometer long breakwater was a technical feat due to its incredible depth of 63 meters it took three decades to construct and cost more than a billion dollars when it opened in 2009 it was the most expensive coastal protection structure in japan but this center of iron and steel has become a shadow of its former self since the closure of its last steel works in the late 1980s when the breakwater opened in 2009 kama ishii was fast losing its population the cost of the breakwater was considered far too much for a city in decline and only two years later the 2011 tsunami delivered the final blow to this ambitious structure foreign came from all over the world to study the remains of this model breakwater and to determine whether the structure did help despite its near total destruction and the results are positive parry the japanese port and airport research institute concluded that the breakwater delayed the arrival of the tsunami's first wave by six minutes and reduced its height from 13.7 metres to eight meters so the wall has been rebuilt at a cost of about 850 million dollars akahama is one of the few villagers to have refused a giant sea wall the initial project was for a wall 14 metres high but it has been lowered to 6 meters small compared to most in the region hitting the opposition is hiromi kawaguchi an unlikely rebel considering what he experienced in his village [Music] um my despite losing his family and his home hiromi kawaguchi organized fellow villagers to decide their future he wanted to rebuild the village without a sea wall or at most have a small barrier one that wouldn't interfere with their livelihoods at first the residents of akahama did not support him why turned down jobs in a government-funded project but after a few meetings they rallied behind him you know foreign foreign [Music] aromi says the sea wall breaks the connection between the residents in the ocean a bomb that has provided him and his ancestors a way of life for centuries [Music] thank you further down the coast other fishing villages have similar concerns about sea walls also feels the wall cuts him off from his livelihood the ocean is [Music] what [Music] [Music] in 2011 a 13 meter high wave left rigazin takada in a state of absolute desolation with 1765 victims this village paid a very high price the government response matched the scale of the disaster in herota bay the once modest four meter high sea wall has now been replaced by one three times the size [Music] foreign these days the only view at sushi fujita's oyster restaurant is the wall but the problem is much more than aesthetic by cutting the inhabitants off from the ocean the wall that is meant to protect them is actually making them more vulnerable to future tsunamis the wall is also damaging their ancestral tradition of oysters rika zentakada's prized product [Music] [Music] foreign foreign giant concrete sea walls are being built on a scale never seen before in a country known for corrupt links between the state and the construction sector the post-tsunami reconstruction is a chance for government to reward construction companies for support and donations it's also a way to boost the stagnating japanese economy back in tarot the students are learning how the faith the residents put in the wall led to disaster the brutal realities of a tsunami are clear and the lesson is flee the moment the alarm is raised do not trust the sea walls can save you a study carried out at tokyo university found that the presence of sea walls added 30 to evacuation times during the 2011 tsunami so while coastal barriers delay the arrival of a wave they also delay the departure of the inhabitants walls give residents a false sense of security every year natural disaster prevention day aims to instill the survival reflexes needed in case of an earthquake or tsunami evacuation plans and ensuring quick and easy access to higher ground have proven more successful at saving lives than sea walls for the 2011 tsunami it was more this collective disaster awareness rather than sea walls that explains why the death toll wasn't much higher [Music] if heading for the hills is good advice for individuals hiromi kawaguchi believes it could be a good solution for entire towns and villages as well [Music] [Music] [Music] are not the only ones to relocate other coastal communities badly hit by the tsunami have moved their homes to higher ground [Music] many areas wiped out by the waves have now been depopulated converted into parks and rice paddies at sushi fujita's oyster restaurant will also soon have to move he says there is no point in building sea walls if they're only going to protect parks and rice paddies despite many questions about the value and the effectiveness of japan's giant sea walls the government is determined to finish them but these efforts to contain the forces of nature come at a great cost to japan's maritime history culture and identity [Music] [Music] you

Channel: ABC News In-depth

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Keywords: Foreign Correspondent, Foreign Correspondent Japan, japan, japan earthquake, japan tsunami, japan tsunami documentary, tsunami, earthquake, japan sea wall, japan great wall, japan sea wall tsunami, abc news, abc, abc news australia, real engineering, smarter every day, japan's great wall

Id: O8KQbZDatg0

Length: 29min 29sec (1769 seconds)

Published: Tue Mar 02 2021