Actually Indy the biggest flood was in the 1893s & again bigger than recent floods early in the 1900s, so the dams may be helping to some extent.

By far the most rain in South East Queensland since white settlement was in 1893. In my district it was 28% more than 1953, the next highest, which was 20% higher than in recent years.

A few years back some engineers were blaming the foundations of Captain Cook Bridge for recent flood levels, although some others reckoned that was wrong.

It's painfully obvious why some things will never improve.

Hasbeen,
I'm not disputing your information but I'm inclined to think that because of dams the surrounding ground is already so saturated that literally nothing more gets absorbed & water simply runs off & floods areas which didn't flood before due to lesser flow volume & faster run-off.
In any case, not building on flood plains will ensure less damage & fewer insurance claims which in turn would slow the pace of premiums rising to un-affordability.
Rebuilding if rebuilding is the only financial option has to change to high-set design. I have a neighbour who is preparing to build as we discuss this & he has built up his foundation by four feet whilst the home next door is at ground level & will certainly be flooded when next we have a normal Wet ! He chose 4 feet because he asked around & learned that the highest recorded flood covered his block by 18 inches. Another home some distance away is built up 10 feet including the carport.

JoNova on her blog has reproduced a graph by the Bureau of Meteorology entitled KNOWN FLOODS IN THE BRISBANE & BREMER RIVER BASIN. It shows that the flood in 1893 & an earlier one in the 1840s reached 8.3 meters, over twice as deep as the current flood at just under 4 meters.

God help the modern Brisbane if another of those should eventuate. 1893 was a wet year! Crohamhurst just inland from Caloundra had 2023.8, twice the annual rainfall, in five days, Brisbane had three floods in two weeks in February and another in June.

Wife and her girlfriend joining 'mud army' today. Not to clean up but make sandwiches and cups of tea etc. Good luck girls.

Building in potential flooding area must be planned far more critically from now on. Whilst there can never be a 100% guarantee for no flooding as in fact anything else, more practical & common sense will lessen the suffering & damage bill. Suburbs need to be designed in a more streamlined spread & most definitely high set homes will help. Water flow must be obstacle free & wherever & whenever the water courses should be widened. There is a challenge for town planners & especially engineers to start thinking if they want to leave a legacy not associated with carnage.
That is why I am a strong believer & advocate for gradually moving people beyond the GDR & particularly around the Lake Eyre basin. It will eventually happen but I think if the move is started now rather than wait till more natural disasters dictate a lot of mayhem & suffering will be eliminated & economical side effect benefits will automatically keep pace.