The flood waters here in England are beginning to abate. Not that the hundreds of thousands of people are anywhere near a return to normal. Running water will probably not be restored for several weeks, houses will take months to dry out and destroyed furnishings replaced, some sodden fields may not be useable for growing crops again for years.
Japan is facing a different fearful possibility demonstrated by a 6.8 magnitude earthquake last week. It left thousands of homes too dangerous to live in. But far more terrifying, the quake was near a nuclear power plant that would not have been able to withstand the quake it had taken place just a few miles closer. Another nuclear plant west of Tokyo is built directly above an active fault line which would result in a nuclear disaster if a quake struck.
Japan itself is a region highly susceptible to quake activity. It has 55 nuclear reactors. None have been built to withstand a severe earthquake.