Abraham Lake, Artificial reservoir in David Thompson Country, Alberta, Canada.

Abraham Lake is a reservoir on the North Saskatchewan River in western Alberta, Canada, created in 1972 by the Bighorn Dam. It runs 32 km (20 mi) along the David Thompson Highway between Saskatchewan River Crossing and Nordegg, with a surface area of 53.7 km² and a width of up to 3.3 km. Its blue colour comes from rock flour suspended in the water. Abraham Mountain, Elliott Peak and the Cline River Heliport stand on the western shore, Mount Michener on the eastern shore and Mount Ernest Ross at the southern tip.

Abraham Lake was created in 1972 when the Bighorn Dam was built on the North Saskatchewan River by Calgary Power, now TransAlta. The dam was planned without public hearings or assessment of social and environmental effects. Flooding the Kootenay Plains submerged the cabins, graves and pastures of the Bighorn band of the Stoney Nakoda First Nation and ended their hunting and fur trapping livelihood. In February 1972 the Alberta government held a school contest to name the lake; it was named after Silas Abraham (c. 1870–1964), a Stoney Nakoda farmer and hunter from Morley.

The name comes from Silas Abraham, a member of the Stoney Nakoda First Nation who farmed and hunted nearby. The turquoise color visitors see today results from fine glacial sediment suspended in the water.

During winter, visitors can walk onto the frozen surface at Preacher's Point to view methane bubbles trapped in the ice. In summer, the shoreline offers opportunities for hiking and boat launches for exploring the water.

The same frozen methane bubbles occur in Siberia's permafrost, but there they lie under deep snow that hides the ice. Abraham Lake sits east of the high Rockies, in a dry climate with little snowfall, so the ice stays visible. Ecologists from the University of Alaska Fairbanks drilled the ice, poured in warm water and lit the escaping gas, which burned for several seconds.