Pink Waterfall

Alberta's Waterton Lakes National Park is the site of Cameron Falls, a stunning waterfall that flows with clear waters on regular days. During periods of abnormally heavy rain, however, the waters are stirred up with a sediment called argolite, which emits a pink colour when light is reflected on it.  The result is a pink waterfall that collects into a reservoir of the same colour. 

Catching the falls in the middle of its colour change is a very rare opportunity. The conditions need to be near perfect in order for the falls to turn pink, so there's no guarantee you'll see a pink waterfall during you next visit.

"Earlier in the day there was heavy rain fall, which isn't uncommon, but the conditions must have been just right to bring down that much sediment,"

However, photographers who have frequently shot at the falls recommend that visitors who do decide to try their luck should go during the rainy season (spring and summer) to increase their odds of seeing it.  

Sources : Google & Wikipedia