Stop wasting water.
Says it all really.
Add to that limit and control the present out of control population growth explosion and we might all have enough.

Water isn't everything. What about soil, which, in Australia, was impoverished thousands of years before white settlement and has been used and abused death by European type farming and grazing over the last 230 years. The best soil is on the east coast, but that's where most people want to live and cover the place in concrete.

Soil cannot be replaced. Much of it is blown away during our regular, inevitable droughts. Nothing water will do to stop that or replace soil that has had everything taken out of it. Halving the population to what it should be is the only answer.

Although this subject has already been over-flogged to hell & back, we still have people who are against drought-proofing the country beyond the great Dividing range.
How many more times does it need to be said. Implement the Bradfield Scheme. Use the monsoonal floodwaters from the northern Qld rivers. Don't destroy the environment, enhance it !
End of discussion!

The Bradfield scheme could be done, but not as Bradfield envisioned it given a pipeline that long and that big would cost billions.

We could do much the same thing with a tunnel high in some tropical mountain rage with a series of very small dams and a few tunnels taking some of the monsoonal rain and injecting it into the northernmost reaches of the Great Artesian Basin.

And for a fraction of the outlay required to implement the Bradfield scheme.

We waste huge amounts of water as effluent that should could support mop crops and as underground irrigation for say, lucerne, all orchards vineyards cotton and rice just to name a few cash crops that would soak the moisture and the tons of nutrient, very safely.

Then there are thousands of capped bores, capped because the water was too salt or mineralised, even though the flow rates were at times impressive. And now available as up to 95% potable water a cost-effective irrigation thanks to space age deionisation dialysis desalination.

Which can also be used on everpresent surrounding seawater for the same or any other purpose. With the salt-laden liquor being able to be treated with electrolysis to separate the salable chlorine from the salable sodium!

We're not short of water just ideas people and leaders with enough intestinal fortitude to back them. We can't make it rain but we sure as hell can drought-proof this wide brown land!

Albeit, not with coal-fired power! Given that would simply be too costly to create a profit! Instead, we just need to crack on with walk away safe, MSR's and thorium, to make all of the above, doable!
Alan B.

We also must utilize appropriate crops, ones that do not use more than their fair share of water in such a dry continent. I question whether Australia can afford a cotton or a rice industry.

https://www.smh.com.au/business/the-economy/our-concern-about-the-drought-isn-t-fair-dinkum-20180821-p4zypf.html