Unprecedented means it has never happened before, which is simply untrue.
I remember severe flooding across the UK for days on end. and it was on TV so it wasn't THAT long ago!
I've been here before, I've watched land that hitherto has been unaffected by flooding become inundated to the surprise of everyone concerned, and yet one only has to consider the effect of civilisation has on the ground infrastructure to realise that water flow has changed significantly and flooding has become inevitable.
As population levels rise upstream then water disposal becomes a problem for them, and so in a usual human reaction they improve the drainage to disperse the waters from their locale and once achieved, care no more about it.
Trouble is, that given enough upstream places doing that, causes excess water to arrive downstream very much quicker than it used to do, owing to the much improved drainage. The result is all the extra water arriving downstream at the same time causing flooding, it is so simple that a child could work it out. So how come it hasn't become obvious to the government planners?
The obvious answer is - it must be, but they have decided to take no action as that would cost money better spent in Iraq, and it can always be written off as acts of god. They are also lined up for a fair increase in income by taxes with all the money that has to be spent to make reparations and inflated insurance premiums all round, so I suppose there is little motivation when it's not actually raining.
I didn't get flooded - this time - but I know that I'll end up paying my share of the damage.
My advice is to pay attention to where the movers and shakers choose to live and avoid the areas they are leaving behind. That's their answer to the problem. 
Agree.
We used to live in Maidenhead which flooded regularly?
The ?solution? was a multi-million Pound flood relief scheme which took all the water directly to Windsor downstream which now floods instead.
You won?t believe this bit tho ? brace yourselves ? the flood relief channel was dug across some of the most productive gravel bearing soil of the country, all of which was previously unavailable because of green belt designations. What a bizarre remarkable coincidence eh?
