What exactly is the 'Lost Locomotive of Kiowa Creek'?

The locomotive that disappeared, separated from the rest of the train, following a train wreck in raging floodwaters near Kiowa Creek, Colorado during the night of May 21, 1878, and has not yet been found.

http://www.unexplained-mysteries.com/forum/index.php?showtopic=41570

That has been disputed. Apparently, the Kansas Pacific was in poor shape financially, and there was an attempt to get both the locomotive and the insurance money. Loco number 51 hasn't been 'found' because it was already removed. It later seems to have reappeared on the Union Pacific, who had taken over the KP. It had been rebuilt as a 4-6-0 and renumbered (as were all the KP engines) 1026. My thought on seeing the question and the above answer was that if the Tay Bridge engine could be recovered and reused, something going into a creek should at least be findable. I know creeks are sometimes not all that small, but until the railway bridge was rebuilt, passengers at Kiowa Creek were able to cross a footbridge to join their continuation train.

https://en.wikipedia.org/wiki/Tay_Rail_Bridge