Moraine Lake is a glacially-fed lake in Banff National Park, 14 kilometres outside the Village of Lake Louise, Alberta, Canada. It is situated in the Valley of the Ten Peaks, at an elevation of approximately 6,183 feet. The lake has a surface area of .5 square kilometres (0.19 sq mi).
The lake, being glacially fed, does not reach its crest until mid to late June. When it is full, it reflects a distinct shade of blue. The color is due to the refraction of light off the rock flour deposited in the lake on a continual basis.
Source: en.wikipedia.org/wiki/Moraine_Lake - 27.05.2010