Peyto Lake is a glacier-fed lake located in Banff National Park in the Canadian Rockies. The lake itself is easily accessed from the Icefields Parkway. The lake is formed in a valley of the Waputik Range, between Caldron Peak, Peyto Peak and Mount Jimmy Simpson, at an elevation of 1,860 m.

The lake is fed by the Peyto Creek, which drains water from the Caldron Lake and Peyto Glacier (part of the Wapta Icefield), and flows into the Mistaya River.

Every day during the summer melt, Lake Peyto receive hundreds of tonnes of fine glacial material known as rock flour. It is very light, and stays suspended for quite some time. When the light hits the surface of these mountain lakes, the suspended material distorts the wavelengths of light, reflecting back more of the green and blue end of the spectrum – sees as emeralds and blues. Also, since each lake gets a varying amount of this material, each lake will have its own shade of blue. This shade will also vary over the course of the year. In the spring, there is little suspended rock flour, so the lakes are the same colour as lakes elsewhere – deep blue. As more material flows into the lake with the spring runoff, the lakes progressively change to their famous colours. Later in the season, as the glacial melt ends, the rock flour will slowly settle, and the illusion will be lost – until next season brings a new supply of the Canadian Rockies magical lake dye.

The Peyto lake is best seen from Bow Summit, the highest point on the Icefield Parkway.




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