The Great East Japan Tsunami: One Year Later - Tohoku, Japan Earthquake and Tsunami of 2011 - page 89

Appendix2
The Great East Japan Tsunami:
OneYearLater
Lesley Ewing, PE. D.CE, M.ASCE
and Catherine Petroff, Ph.D. PE, M.ASCE
The eleventh of March 2011 was a day of profound sadness for Japan. One year
later, Japan is still working on clean-up and discussing recovery options. At the
March 5th and 6th JSCE 2011 Great East Japan Earthquake Commemorative
Symposiums discussions on community recovery emphasized sustainability,
resilience, redundancy and ways to address the unexpected. The current national
tsunami policy has developed a two-phase approach - design for full protection
against the 100-year level event and develop life safety approaches for the extreme or
1,000-year event. As part of this approach, a Work Group on Embankment design
has recommended designs with more protection from direct wave attack as well as
better landside protection against overtopping failure. Another group that is focused
on planning for the redevelopment of the Sendai plain has proposed a double line of
defense with levees/embankments as the seaward-most element and elevated
roadways as a second line of protection, with all the residential development located
on high ground inland of the elevated roads. Such an approach is not without
problems. Many of the people living on the Sendai plain make their living from the
sea and the inland relocation will be a daily inconvenience; an alternative approach
suggested at the workshop was to provide tsunami-resistant high-rise buildings to
allow continued access to open water.
After the Symposium, on March 9 th and 10 th , we traveled back to the Tohoku area
with Dr. Yuichi Nishimura of Hokkaido University, to revisit some of the
communities we had surveyed ten months earlier. As seen in the following photos
(May 2011 view on top and March 2012 view on the bottom), sand bags, mesh rock
bags, embankments and other temporary measures filled openings in shore protection
- not to replace prior protection but to temporarily prevent routine waves from
making conditions worse. Clean-up efforts had progressed and many sites were
cleared of debris. Much of the debris remained, stacked in large mounds near the
devastated areas. New power lines had been installed, and much of the road damage
had been patched up. Railroad tracks were being replaced and roads with collapsed
bridges had been rerouted. The ice plant at Taro had been rebuilt; fish markets were
reopening and rice paddies were regraded; there was a new gas station in Rikuzen
Takata and a temporary shopping area in Minami Sanriku: but few permanent
structures had been rebuilt and many people continue to live in temporary housing.
Recovery from such an enormous event is not a short-term effort.
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