You’re confusing 2 issues when it comes to Australia’s water usage. The first is the Murray Darling Basin, which is the 4 state disaster you’re talking about,

You’re confusing 2 issues when it comes to Australia’s water usage. The first is the Murray Darling Basin, which is the 4 state disaster you’re talking about, and the many poor outcomes it has created. I grew up (and my parents still live and farm) about an hour south of the QLD border. Different regulatory frameworks means NSW farmers can pump with QLD farmers can’t. And we’re talking pumping from the river, and that’s what creates downstream problems. Particularly when farmers on one side can pump and ones on the other can’t. The Great Artesian Basin is a different story. It requires pumping and drilling and is regulated totally differently. Probably the biggest changes have been the significant cuts to water licences, but even moreso was the capping of free flowing bores that occurred in the 90s and 2000s. Artesian basin pressures have been generally stable or rising across the last 10-15 years, reflecting stabilisation of consumption-recharge cycle - even in the face of 2 of our worst droughts on record. The largest contributors to drainage have always been stock bores, as agricultural/centre pivot usage got off the ground a lot later in Australia than in the US, and so the regulatory framework wasn’t so far behind usage and didn’t create a tragedy of the commons scenario as in the MidWest USA