There are two possible solutions to prevention of flooding of properties and both are being done in other parts of the world.
The Dutch who have large parts of the country below sea level and are at risk with sea level rise have devised a method of building on hollow concrete pads that will float.
It takes the place of the traditional solid concrete pad and though it would be more expensive would give a lot of peace of mind and also would no doubt reduce insurance costs. Services are supplied via flexible cables and pipes and of course the pads are moored to large piles that will keep it in position in a flood situation.
Parts of the US also use this approach as well.
The other approach would be to build levy banks around a town to divert floodwater away.
It would be expensive again but will cut insurance costs and should raise the value of the properties that are protected

The Dutch idea of a floating raft floor is a brilliant idea for new dwellings (Sarnian). What becomes obvious to TV viewers through this disaster period (Qld) is the “infilling” under elevated houses: An illegal practice in NSW flood zoned areas I am acquainted with. Simply changing planning laws prohibiting this practice would make a huge saving in property losses and reduce engineering stresses on those properties by allowing free flow of water underneath.

Also in my experience in NSW, special grants were made available to owners of properties in flood zones enabling elevation of existing buildings to a specified height above previous major flood level events. (Lower floor infilling illegal)!
And here is an idea from left field; why not mandatory life jackets in all houses in flood zones, a very simple and inexpensive innovation that would save lives in a dire emergency

diver dan.....how about the world is changing, and your not smart enough to admit it:)

Hello....Ban-aid required here:)

I just love it, when Bull is for free:)

Please dismiss my everything,.....the world will be fine, just ask what ever you believe in.

Oh Dear!

BLUE

the Netherlands are in line for the next huge flood disaster.

Can you imagine the catastrophe as hundreds of cement pontoon mounted floating houses piled up against the bridges, both above, & just below the water?

hasbeen,
there are things called moorings which do quite a good job. they even use them to keep drilling rigs in the one place at sea in all weathers even in places like the North Sea and Bass Strait.
It would be obvious (to most people) that you would not attempt to use the floating house concept in an area where you are likely to get very strong flows. Some of the Brisbane suburbs would be an ideal place for this concept, the water came up quite placidly and then retreated the same way.
One size does not fit all