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I grew up in the Risle Valley, that is pictured in the video. I can confirm that we have the same geology. For only a few years, the river is disappearing every summer, which sounds surprising in a global warming context. But no big deal here, just geology.

The article says it's karst.

(Sinkholes occur when an already-significant underground cavity, typically formed by water dissolving the rock, gets close to the surface and the roof falls in.) https://en.wikipedia.org/wiki/Sinkhole

Lake Chesterfield?

Yep! We've since moved, but they have the lake drained right now to try to figure out how to make it stop leaking.

I feel sorry for the "lakefront" houses that have a big empty pit in their back yard. They've tried several times to fix this, and I'm pretty certain that there was a special assessment associated with each attempt.