Why have hurricane areas not considered amphibious development?

After Katrina devastated New Orleans and the surrounding areas, the rebuilding process has been going along full-steam with new condominiums and other types of buildings. Question is, would these new structures that are costing millions from the government and private sector going to withstand another flood?
Personally, I would say no. They’re probably just building the same old housing type of complexes that will be wiped out in the next big storm.
Why not consider some new architectural designs?

This is why I don’t understand this outrageous spending behavior by both government and private sector. Actually, it’s easy to justify private sector because they get subsidized by the government. Yet no one is bothering to calculate into costs that there are many new design structures that could turn New Orleans, along with Florida and other hurricane beaten areas into “floating” cities.
The Dutch have designed housing allow not only houses to float, but entire city blocks. Since the foundation is hollow, it acts similar to a ship and floats when the area is flooded. To not have the house float away, there are posts that act as anchors and just allow the house to move up and down with the water (up to 5 meters).
Now if we’re spending millions of government spending, where there were $8 bottles of water during the rescue operations, then why can’t we adopt technology such as this to prevent such tragedy from happening again? The housing in hurricane and flood watch areas should be designated with amphibious housing development only. This would at least provide some infrastructure left instead of rebuilding every time a major catastrophe comes through and wipes out entire cities.