Even the most ardent hermit knows, by now, that the USofA west of the Mississippi is in some level of drought, and that central California is about worst off. It is widely reported that about 80% of the managed water in the state goes to agriculture, and that a disproportionate amount of that goes to grow almonds. About 80% of the globe's total almonds are Californian. How could such a dry, hard nut squander so much water? No idea.
In the news recently were the water restrictions from Sacramento, and government generally, and the flouting of such measures in places like Beverly Hills. The 1% must have their emerald cities.
As proposed here much of the time: data is useful in predicting the future when the process under study follows God's (or Nature's, as you prefer) laws. Such laws are immutable and play no favorites. We just don't always know the full and exact state of those laws. There may no longer be any meaningful ignorance of Mother Nature's rules in our macro-world. Nothing new to learn, in terms of laws themselves. Our understanding of climate change or global warming or kiss you ass goodbye, is not due to finding new natural law, but rather of having sufficient data to track thermodynamics on a global scale at ever finer granularity.
Processes which follow Man's laws are a different matter entirely. Some of us, our betters, get to change the laws when their enforcement limits our betters' behaviour. We see this in the very upscale parts of the LA basin, where those brilliant green lawns and such continue to be husbanded with lots of H2O. Fines seem to be ineffective. Shaming appears to be the next step. Good luck with that.
But let's think about the issue. Water, whether in a stream, river, lake or aquifer, doesn't exist within Man's artificial boundaries. If I drill a well on my 1 square foot of land, the water I draw doesn't come from just that 1 square footprint projected into the earth. It is drained from any contiguous groundwater in all directions at any distance which gravity makes available. It is a common resource. The same for natural streams and rivers and for natural or man-made (generally, dammed flows) lakes/reservoirs. All that Poland Spring bottled water you use is drained by Nestle` from community resource in central Maine. Some citizens are none too happy about turning a community resource into private profit.
Those that squander a common resource should, by rights, pay more for the resource. Pay more, in fact, such that the rest of the community can replenish the wastage. In California, these days, that would be one hell of a bill: bringing train loads of water from Canada or New England (though my part of it hasn't seen rain for a few weeks; knock on wood) will cost a pretty penny. The 1%, of course, won't abide such horrible treatment. Since most of them, by legend of course, are think-workers who don't need to be in California to be rich, if they're made to pay for their self-absorbed squandering will just pull up stakes and go someplace that has lots of water. The 19th century approach: if you don't like it here, get the hell out and move on. There's not much virgin territory left in the USofA.
But, what if the states made a pact? Since water, in every state (and across them, too), is a common resource, why not ban water squanderers from moving into some other state? NIMBY, but with a purpose. Group homes for the mentally challenged are routinely blocked from neighborhoods, due to threats of violence (perceived) or low level disruption. Why not change the incentive, which now permits the few to impoverish the many with respect to water? We're doing that, sort of, with air; although those laws are aimed at sovereigns and industry for the most part.
"You're a convicted water waster. You may not own, live in, or occupy property in this state." Now, that's incentive.