I was talking to a friend of mine a couple of weeks ago, and he was expressing surprise that the tsunami damaged the Fukushima Daiichi power plant so severely, particularly as there was a large seawall built to protect it:
What neither of us knew at the time, was that the earthquake lowered the coastline by approximately 3 feet, so a 30 foot tall tsunami wall was reduced to approximately 27 feet, and then faced a wall of water that was over 32 feet tall.
No match.
Miyako before:
Miyako after:
The tsunami walls withstood the force of the water, but were simply not tall enough after tectonic modifications to the landscape. In numerous images, there is obvious evidence that the inrush was more than 3 stories tall, with cars left stranded atop 3 story buildings:
In other cases, the entire three stories of buildings have been stripped of nearly everything but the structural steel skeleton:
There have been over 500 aftershocks, many larger than the 6.8 Nisqually quake of February 28, 2001 (here in Seattle). The fact that anything is left standing at all is an amazing testimony to good building practices in Japan.
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