A lot of the people who lived there were both aware of the risk and prepared for some degree of flooding. They were not, nor could they reasonably have been expected to be, prepared for this:Yuno Gasai said:But in addition to feeling sorry for you, I will question your choices. Particularly if it is revealed you were aware of the flood warning risks in your area, and chose to ignore them. I get it's easy to adopt the "it'll never happen to me" mentality, but that doesn't mean you shouldn't be prepared.
Hopefully these people will learn from the floods and will be better equipped to deal with them next time. Or will move out of flood risk zones. Whichever.

This isn't a case of "what did they expect?" This was unprecedented.
Sorry for banging on about this, but as I said before, I grew up in the area. I know what the risks and reasonable expectations are. It really irks me that people would suggest this is anything other than a disaster and that the people living there should somehow have been prepared for this.