Texas is screwed.

[True Federalist (진정한 연방 주의자)]

And as water prices rise there becomes a high profit motive to build something like a water desalination plant.

And as water prices rise, there will be added incentives to be more efficient in using water, or even abandoning some uses.  The problem is, I don't think the incentives to do either will be there until the aquifers start to run dry, at which point there will be a sudden shock to the system.

[True Federalist (진정한 연방 주의자)]

And as water prices rise there becomes a high profit motive to build something like a water desalination plant.

And as water prices rise, there will be added incentives to be more efficient in using water, or even abandoning some uses.  The problem is, I don't think the incentives to do either will be there until the aquifers start to run dry, at which point there will be a sudden shock to the system.

Well there are incentives to do both. Be more efficient with it and innovate a solution. I would grant that municipal regulations that put a damper on a utilities ability to raise prices significantly as the water is running low may exasperate the problem(I don't know if this is much of an issue in a state like Texas), but the cost of extraction should rise as the water level drops, right?

Most aquifers are only a few hundred feet thick, so except for the most shallow of aquifers, the added costs of drilling deeper to reach the bottom of the aquifer will be negligible.  Some places will be lucky enough to have another deeper aquifer that they could draw on, but accessing it would be a sudden jump in cost, not a gradual one.