I guess, however, there is yet another category: mineral water towns that were laid out but never actually populated. Silver Springs in McDonald County, Missouri, appears to be such a town. The place was surveyed and given the name Silver Springs in August of 1881 by a couple named William and Arzelia Harness, but that's about as far as the venture ever got. Sturgis's History of McDonald County tells the story in vivid language of what happened afterwards: "The seasons came and went. William's beard grew grizzled, and the cheeks of the fair Arzelia lost the pink tint of youth, but adversity flapped her wings over the enterprise, and their bright dreams of stocking legs filled with the shining metal vanished for aye--and the water still trickles through the gravel as of yore."
The county history places Silver Springs in Section 6, Township 22, Range 29, but I haven't found it listed on any maps and I'm not familiar enough with the townships and ranges of McDonald County to know where the place was located (or was intended to be located).