Clarence River water diversion to SE Queensland more expensive than Traveston Crossing Dam

The recently released Traveston Crossing Dam Environmental Impact Statement cites a dam on the Clarence River diverting water into south-east Queensland at Wyaralong 2007-2056, as being $650-51 million more expensive than building a major dam on Queensland's Mary River and also more expensive than a desalination plant on the Sunshine Coast.
See link:
http://www.coordinatorgeneral.qld.gov.au/library/pdf/
Traveston_Executive_Summary_171007.pdf

From a Queensland perspective, this would cost such a Clarence diversion at an estimated $1,0340 million.
On economic grounds, it seems that Messrs. Howard and Turnbull have backed the least preferred option.