Whitewater forms in the context of rapids, in particular, when a river's gradient changes enough to generate so much turbulence that air is trapped within the water. This forms an unstable current tha
Whitewater on the river Guil (French Alps)
Whitewater on the small rapid of Kannonkoski, Central Finland
Vivid water of the Torne River between Sweden and Finland.
The international scale of river difficulty is an American system used to rate the difficulty of navigating a stretch of river, or a single rapid. The scale was created by the American Whitewater Asso