Abraham Lake

Abraham Lake was created in 1972 by the Bighorn Dam and floods a valley of drowned vegetation. Bacteria decomposing that plant matter on the bed release methane, which rises in bubbles; when the surface freezes early and the air stays cold and still, the bubbles are trapped and stack under the ice in white columns of discs, largest near the bottom and smaller towards the surface. The effect needs clear ice, which means cold before snow, and it does not appear every year. Wind scours the lake, which helps keep it clear. The turquoise summer colour comes from glacial rock flour.

What you actually see

• The frozen bubbles - stacked methane discs suspended in clear ice.
• The clear ice - wind-scoured surface with visibility metres down.
• The turquoise summer water - glacial flour colouring the reservoir.
• The David Thompson corridor - the mountain highway along the shore.

When to go

January to early March, and only in a year when cold arrived before heavy snow; some winters produce no visible bubbles at all. Summer visits show a turquoise lake and nothing else.

Honest expectations

The ice is genuinely dangerous, with pressure cracks and thin sections, and people have gone through; local guides know the safe areas. The bubbles do not form every winter. Wind chill on the exposed lake is severe.

Nearby

Nordegg lies east; the Icefields Parkway is west.