Dear Jennifer,
I feel compelled to alert your readers to the significant property developments occurring in the vicinity of the Lower Lakes in South Australia.
There is the canal development on Hindmarsh Island with pictures at this link:
http://tmhi.com.au/home/
The ‘Wellington Marina’ development occurred during the drought. No water at all on these ‘waterfront’ blocks when the levels are minus 1m AHD. And my guess is that even at sea level, hardly a tinny would float. The Wellington development has houses on it that look maybe 10 years old:
http://www.wellingtonmarina.com.au/index.htm
This other one, ‘Mannum Waters’, was approved by the state government during the height of the drought. It’s a big one and the city of Mannum appears to be welcoming it to boost tourism.
http://www.mannumwaters.com.au/
At ‘Milang Bay’ it’s not canal style, but lake front:
http://www.sarahhomes.com.au/land_dev.php#MILANG
Then there is ‘Pelican Shores Estate’, again not canal style either, but dependent on water at Clayton Bay for water views. No website but a lot of blocks for sale.
There must be a lot of money tied up in these developments!
Of course they depend on the river being at an artificially high height above sea level.
What I mean is that these developments depend on the barrages maintaining what you have correctly described as an artificial freshwater lake system.
Most Sincerely
Charlotte Ramotswe

Jennifer Marohasy BSc PhD has worked in industry and government. She is currently researching a novel technique for long-range weather forecasting funded by the B. Macfie Family Foundation.