Ground elevation project in Rikuzentakata expanded without examination

JAPAN (The Japan News/ANN) -- Involving a massive tsunami and a nuclear power plant accident, the Great East Japan Earthquake was an unprecedented and complex disaster.
This year marks a decade since the disaster occurred in March 2011. As symbolic moments we still remember are examined once again, untold stories have come to light. This is the first installment of a series featuring such stories.
This spring, a civil engineering reconstruction project is finally scheduled to be completed.
The project is to elevate the ground of Rikuzentakata, Iwate Prefecture. An area as large as 2½ times the size of Tokyo Disneyland is being

A conveyor belt to transport earth and sand from higher ground, foreground, to the area being elevated, rear, is seen in Rikuzentakata, Iwate Prefecture, in August 2015.   --Photo Yomiuri Shimbun file photo

raised to 10 meters above sea level using earth equivalent to nine times the volume of the Tokyo Dome.
This is one of the gigantic projects being undertaken in disaster stricken areas, but the initial plan was to raise the ground only 2 meters. Over about two years, the scale of the project has been expanded five times.
A tsunami more than 10 meters high hit the city’s vast downtown area, killing 1,606 people there. About 4,000 houses, half of the number in the city, were damaged by the disaster, and the city lost all its functions. At that time, local residents earnestly wanted efforts to be made to prevent their towns from being devastated by such a disaster again. So they sought to make them stronger and more resilient.
Civil engineering methods are limited. To make the area more able to withstand future disasters, there are only three options: building a seawall, relocating the area to higher ground and elevatingRikuzentakata Mayor Futoshi Toba initially requested that the Iwate prefectural government build a 15 metre high seawall. The ground was also set to be elevated, but at that time, the main purpose was simply to restore it to its pre-earthquake height, so the ground was only going to be elevated to 2 meters above sea level.
However, the height of the seawall decided by the prefectural government was 12.5 metres. The prefectural government determined the height based on the conclusion that disaster mitigation would be possible in combination with proper evacuation. Plans to develop residential land were also studied, but there was no suitable land to relocate housing to. This left the city with only one option.
The Reconstruction Design Council, an advisory body for the prime minister, has also advocated implementing various measures including elevating the ground to ensure multiple forms of protection. Given this, the city government anticipated that it could obtain state funds and changed the planned elevation height to 5 metres above sea level in the autumn of 2011. From this point on, the scope of the project began expanding.
Backed by the mayor, who said, “It is meaningless if people say it’s too scary to live there,” the elevation height was changed again a year later to an average of 9 metres above sea level.
The change stands to reason. As the JR Ofunato Line was expected to continue running through the low lying area, a multilevel crossing was planned for roads in the center of the city.
This would have required sufficient height, but it was thought that earth and sand generated by the construction of residential land on higher ground could be used.
At any rate, the central government had asked for local disposal of that earth and sand out of concern over the cost of transporting it.

(Latest Update January 16, 2021)