Very interesting map. I found this while I was looking for the strong ground motions. The only thing interesting to me will be the PGV's under those nuclear plants. Maybe they wouldn't be in trouble if the back-up generators had started up, but those things never work in an emergency, and I really can't see they could be knocked out forever by a little splash.
Here is the 30 foot (10 m) zone. That's the height of the tsunami. This is just a map product, and is not the actual overflow zone.
Note that this earthquake hit a 'relatively unpopulated' area, if that can be said of Japan.