Why put good, clean drinking water through a cooling system at a power station when perfectly adequate water is being thrown in the sea within a 60 mile pipeline distance? [ Come to that, why purify water to superb drinking-quality standards and then use it to flush toilets or wash cars, but that's for another argument.]
They are not talking about pumping sewage. The exit water from the Melbourne sewage plant[s] will have been through a process of gross solids settlement, then activated sludge aeration and then final settlement before release. This water is not quite drinking quality, but neither is rainwater! A reservoir and filtration/chlorination plant must be used to make it so, [at a cost], and Latrobe already have one. I bet the guys at Melbourne Sewage Treatment are proud of their effluent quality and would consider it an insult to impune its quality.
The River Thames in England is a good example of treated water re-use. By the time the river-water reaches London, having passed Oxford, Reading, Maidenhead, Taplow, Slough, Eton, Windsor, Staines, etc., it has been drunk at least 6 times. It is clean water, established by the fact you can now see trout swimming around Tower Bridge.
The idea that an established modern sewage plant could suddenly 'reduce the water quality' to reduce costs is bloody ridiculous. The only way to do that would be to pump raw sewage. Besides, there would be contracted standards imposed on BOD, nitrates and suspended solids on the water supplied, in order to protect the power station plant.
Meanwhile the better quality water goes to the city, and it costs less. The folks at Latrobe will still be getting clean drinking water from their present supply arrangements, since there has to be an excess to make the scheme work.
Unless there is a good cost advantage, this scheme will never get built. How can that result in higher charges to consumers?
Wood work but can't!