Just about any dam and/or bridge you look at on Google Earth has that distorted look.
You can’t really tell that kind of stuff that’s being claimed in the article from Google maps. I use Google Earth a lot at work and it’s decent for ballpark estimates, but I’d rely on surveyors for anything where precision is needed.
Take for instance, I can export topo from a Microstation file (from surveyors) and import into Google Earth using surveyed anchor points and the imported file never exactly matches with the satellite imagery. Add in the 3D projections from Google Earth and things can get pretty wonky.
Using Google Earth for this is silly. These distortions are artifacts of stitching together satellite photos. A proper survey / LIDAR is cheap & easy and will tell you when deflections of a few mm are happening.
I’m the wrong type of engineer, but I believe most dams like this will have built in deflectometers (inclanometers) wired to the SCADA and alarm at set trigger points. The alarm bells would be going off long before any movement was viable to the naked eye.