The aqueducts that farmers are tapping into now take /millenia/ to recharge. This is not your standard couple-hundred-foot backyard well; these are /two-thousan

The aqueducts that farmers are tapping into now take /millenia/ to recharge. This is not your standard couple-hundred-foot backyard well; these are /two-thousand foot wells/ dug to the lowest aqueducts just above the bedrock. Once they are tapped out, that water's gone for virtually ever. If the material in the aqueducts is clay, the clay will compact, removing its ability to hold water /forever/. Rainwater only replenishes the aqueducts nearest the surface, and even then, not at a necessarily rapid pace, especially if wells are tapping into those aqueducts.