The hole in the water is real. Not caused by nature, but real. It is a water overflow for a damn. if the water gets too high, it runs into the hole and out the other side.
Here is an example of a much larger one.
http://www.liveleak.com/view?i=a1b_1236032387
Here is an example of a much larger one.
http://www.liveleak.com/view?i=a1b_1236032387
