Fog Blog Canada Log: Nova Scotia Lake Almost Drains Completely:

Waterfront property is a bit harder to find this year in Oxford, N.S.

A kilometre-long lake near the town has mostly disappeared as much of its water has drained into at least two sinkholes in recent months.

"This is pretty shocking," said Amy Tizzard, a regional geologist with the Nova Scotia Department of Energy and Mines. "I couldn't believe my eyes at the extent that it had emptied. Each time I visit there's something new exposed."

CBC has agreed not to name the lake, which is about two kilometres from the town, because officials fear it will attract ATVers and others who could disturb local bird habitats and ongoing environmental studies at the site.

It is the latest sinkhole problem in the area. Two years ago, part of a park and adjacent parking lot in Oxford were swallowed up by a sinkhole. Last fall, the provincial government began investigating possible sinkhole activity beneath a nearby section of the Trans-Canada Highway.

Two aerial images showing a sinkhole (the dark circle), likely responsible for draining part of the lake. The top image was taken in 2020, the bottom in 1939. (Mike Johnson — top image/Nova Scotia Government — bottom image)

Aerial images of the lake show at least one visible sinkhole. Tizzard said the sinkhole isn't new — it has appeared in images dating back to the 1930s — but it appears to have recently reopened.

There is most likely another sinkhole at the other end of the lake, where the water level is also steadily dropping.

Tizzard said the lake is known locally to have fluctuating levels, but the water hasn't been this low since the 1970s.

Exactly where the water is going is a bit of a mystery.

"There'd be a big enough pore space to accommodate the size of the lake," Tizzard said. "So we're looking at caves and fractures or fissures. That's where it's gone. We don't know if it's coming out anywhere yet."

The sudden draining is likely due to the water eroding a layer of gypsum, which would have been acting as a plug.