Backing up a minute to the DNW&P:

I want to understand this, and this is why I ask. In the early 1970s, I visited the east end of the Moffat Tunnel, and on the north side of the D&RGW line, near the east portal, I found an abandoned railroad grade that climbed up the mountain with a lot of curves, and seemed to head generally west. If this was the DNW&P, I understand that this line became the Denver & Salt Lake, and operated until the Moffat Tunnel was opened in 1928.
I followed the grade for a couple miles or so. There were ruins of trestles lying in canyons as heaps of rotting timbers. Eventually the line came to a short tunnel that had caved in or was plugged solid. A couple hundred feet east of the tunnel, on the north side of the roadbed, was what appeared to be the remains of a lineside water tank, but the tank was a rectangular box instead of the typical cylinder shape. Was this the DNW&P line? Did they use square water tanks? Or, as John mentioned, is this the one and only square tank that was used by the construction contractor? What is this location like today?
The ruins of this tank were standing, but the tank structure was quite broken open. It may have once had a cylindrical steel tank inside of it, but there was no evidence of that. The box structure appeared to be very robustly constructed, with big timbers, long steel rods, bolts, nuts, etc.
RK