Option 1: Haul water in by tanker.
Option 2: It's common that there's a second or third aquifer in addition to the depth the existing well is located. If there's a deeper aquifer, extend the existing well. Compare the capital cost of extending the well depth versus the operating cost of hauling. If there's a shallower aquifer, the water is likely to be lower quality. Water treatment technologies may or may not be economically competitive to the cost of hauling.
Consult with a well digger or water witcher in the area regarding typical aquifer availability in the area. Good chance the local well digger is or knows local witchers of good reputation. Alternative is to engage a local and higher $$$ hydrogeologist.
Option 3: Sell out as a friendly repo. It's usually a better deal to the mortgage company than a homeowner taking a walk because the water hauling cost is too great for the homeowner to sustain. Possible that the value of the land alone would be a better negotiated outcome than the hassle of a total walk away and the homeowner may take a lessor hit to credit rating.