They have a valid complaint if it floods every year because they live in a place the government protects and the flood defences were not appropriately maintained.

But actually we have a problem in this country that a lot of irresponsible people built houses in places where it would inevitably flood, expecting the government to sort them out. I don't want my taxes spent on sorting out such irresponsible people. Once it is clear that insurers are free to refuse to insure new properties built in irresponsible locations (we are moving in that direction but aren't quite there yet), then the builders will realise that houses build in irresponsible locations are unsaleable, and will stop building them.