Mega-buildings are now slowing Earth's spin

Snopes covered this in 2021. https://www.snopes.com/fact-check/china-three-gorges-dam/

JPL news release from 2005 at https://www.jpl.nasa.gov/news/nasa-details-earthquake-effect... about the work by Richard Gross and Benjamin Fong Chao.

Benjamin Fong Chao's 1995 article 'Anthropogenic impact on global geodynamics due to reservoir water impoundment' at https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/95GL... ("We compute the effect of 88 major reservoirs on length-of-day, polar motion, and low-degree gravitational coefficients")

Plot point for evil person disaster movie: large masses are staged above super long vertical tunnels. The masses are released at the same time and increase the Earth's rotation speed to cause something bad to happen. ;)

The first mention of this I saw was linked to the filling of the 3 gorges dam in china, and the sattelite used could also see the emptying of the great plains aquifier, But what occurs to me now, is that there is speculation about black holes that might be zipping around, in or through the earth, but those would show up on all of the new gravity detectors, raising alarms instantly so, thats something else to put to bed

By amounts so small as to be effectively zero even over the span of centuries. The article admits that tidal forces from the moon slow earth's spin by orders of magnitude more.

Big, steaming, juicy nothingburger