A television election ad featuring B.C. Liberal Leader Christy Clark touting the virtues of her party appears to feature footage of an Alberta lake.

Sharp-eyed CBC viewer Otto Langer was watching the Washington Capitals versus Toronto Maple Leafs hockey game Thursday evening when he noticed the commercial containing images of Peyto Lake, which is located in the Alberta icefields.

"There is a photo of spruce trees and a lake," wrote Langer in an email to CBC News. "That is not a picture taken in B.C. It is indeed Peyto Lake in Alberta (Banff Park)."

A screen grab of the lake featured in the B.C. Liberal Party campaign ad. (B.C. Liberal Party)

Peyto Lake, Alta. (Syeda hira/Wikimedia Commons)

Langer appears to be correct.

Peyto Lake, which lies along the Icefields Parkway north of Lake Louise, has three distinct points at its north end which are clearly visible in the Christy Clark ad.

The Alberta lake is on the screen for five seconds while Clark talks about balanced budgets.

Other viewers also noticed the blunder and have posted it to social media.

B.C. Liberal Party spokesperson Emile Scheffel says a Vancouver-based videographer produced the footage.

"Of the 16 video clips in the ad, 14 are original and two are stock, including the one you pointed out," he wrote.

"When using stock footage in advertising, we search for B.C.-sourced material. In this case, the footage was ... tagged by the provider as "British Columbia."