> Even if you did it under existing laws, the amount of money required to resume all the properties would be immense.
IANAL, but as I recall, the guarantee that forced acquisition occur on just terms only binds the Commonwealth, not the states. Queensland may not have just-terms laws, and even if they do, Parliament would be able to suspend them.
IANAL either, but anything that happens with regards to forced property acquisitions also means the person with the confiscated property has to be compensated fairly at full market value for said property. And the cost of acquiring all the riverfront property along the Brisbane and Bremer Rivers would be astronomical.
So they only way to resume the properties and provide a benign area for flooding is to either (a) borrow or tax a lot of money for the acquisition or (b) suspend the laws and steal the properties from their owners by means of modified legislation or other force.
I'm not saying that forced property acquisition should never occur, clearly there needs to be cases where this happens ('The Castle' notwithstanding). But to forcefully acquire all the property along the Brisbane river? Another flood mitigation Dam would be a lot cheaper and keep a lot more people happy, and provide more water for droughts. Queensland is still woefully under-equipped for long dry periods. Wivenhoe was designed to mitigate flood waters and guarantee supply until 2000. SEQ needs another large dam.
> IANAL either, but anything that happens with regards to forced property acquisitions also means the person with the confiscated property has to be compensated fairly at full market value for said property.
What you say is true of acquisitions made by the Commonwealth. The Federal Constitution makes that explicit guarantee (Section 51(xxxi)) -- incidentally the High Court have taken the view that "just terms" does not necessarily mean "at market rates". My parents got diddly poop for land compulsorily acquired by the Whitlam Government near Darwin.
But the states are not bound by that guarantee and each State Constitution may or may not have requirements for just terms acquisition by the states. Moreover, State constitutions are generally amendable by State Parliaments without requiring a referendum, making them much less robust to policy pressure than the Federal Constitution.
If it so happens to be that Queensland's "just terms" rules are in an amendable constitution or are an Act of Parliament, then there would be no legal barrier to the Parliament removing or drastically reducing compensation for compulsory acquisition of land.
However I suspect land along the Brisbane river will not be acquired because of the politically poisonous nature of compulsory acquisitions generally.
IANAL, but as I recall, the guarantee that forced acquisition occur on just terms only binds the Commonwealth, not the states. Queensland may not have just-terms laws, and even if they do, Parliament would be able to suspend them.