The environmental cost of desalination is higher than the economic one. Saving water from run- off is cheaper, simpler & safer.
Just keep the 'experts' away & just do it.

All farmers must hang in there and not give up.

Yes some people on fb refuse to wake up, for example anti live sheep activi$t$ that can't figure lack of refrigeration requires live animals to take home to feed families, instead of killing in Australia.

PM Malcolm Turnbull has had a $10 million grant to make rain in a cloudless sky. But he has now gone to ground. Maybe after getting some clues here on OLO he is into ocean chemistry and algae.

I think the future for farming will involve manipulating ocean and lake algae to make clouds and rain. I have photo evidence of algae linked to precipitation. It would be cheaper than pumping water that is so heavy to lift.

Desalination is a reasonable option for small island communities but not for large mainland towns. The power requirements are massive as is the chemical usage & machinery service.
The overall waste product from production of equipment to final brine outflow is not what i'd call economical nor environmentally sustainable. Just ask those who maintain equipment in that industry.

Out in El Nino waters where I have been living and observing 6 months a year, observing algae associated heat since 2008, it appears there is an association between algae and weather.
Concerning topic of this OLO thread, that observation leads me to think the best way to sustain water supply to farmers is to manage the nutrient load that proliferates ocean algae.
However I think there will be considerable delay in establishing such management (to control El Nino events) because media that is driving government policy is not even acknowledging world ocean fish population and ocean ecosystem devastation.

Government has aquaculture policy not ocean ecosystem policy. Media focus is on renewable energy policy, not on world ocean devastation.

Government is not yet seeing or admitting that sewage including industrial animal production nutrient pollution is occurring and causing damage.
Government is not admitting nutrient pollution is the fundamental cause of world ocean fish depletion.

Government is not seeing that the same cause of world ocean fish and ecosystem devastation is ALSO the same cause that is changing weather and climate.

While future advances in science most definitely will give us other methods and other ways to pump water, surely we should not pump our sewage treated or not in the ocean? and yes we know we have a dry hot country and that droughts are always here in some place, every achievement must first take the first step, if we treat this as we would if it was a war we would soon find the money to start

JF Aus,
Control pollution of the oceans & get some control over the weather. Algal proliferation is a direct result of pollution & it should not require a scientist to work out that it is the core of our environmental problems. if only education could be pushed up to a basic level, more people would be receptive & curb the present mentality of out of sight, out of mind.
Methane does to our Air what sewage does to our oceans. Industrial emission is not far behind the pollution caused by mass travel.
I observed algal growth smothering healthy coral at the northern extreme of the great Barrier Reef. I put that down to outflow from that Goldmine in PNG, tourism (Sunscreen lotion) & I suspect seepage of chemicals from mainly WW2 wrecks in the Coral Sea. Commercial shipping has in my opinion hardly any impact.
The biggest impact by far in my book is from Mass tourism.