Yup, saw something similar a long time ago, but can't remember where. The thing was that the water was flowing uphill. It was so strange I walked down to get a closer look and looking toward the origin of the river, it flowed downhill until just before the spot where it flowed up hill. It was flowing so fast the uphill flow wasn't a problem. Sure looked strange from a distance though.

"We don't have any law here. Just a graveyard." LL from TREASURE MOUNTAIN