Where you believed the water tower was near the station site and the 'wire' buried in the ground, may I suggest this might likely have been a grounding cable for the WT. The whole area had likely been cleared of vegetation of any height so the WT would have been the tallest item around so in all likelihood lightening protection would have been installed and this might be what the cable was for. I saw lightening cabling once 30 odd years ago, and this was new material, so no idea if material the age of the WT would have been made the same way. It was a very distinctive cable. Most cabling the strands are twisted and fairly tight together. The LP cabling, as I recall, was looser with less of a twist and the strands had, for lack of a better way of describing it, small barbs (not sharp) horizontally to the strands. I think the idea was encourage the voltage to flow more evenly along each strand also accounting for the looser construction of the cable.