I don't recall hydroelectric plants leaving entire regions uninhabitable.
https://en.wikipedia.org/wiki/List_of_hydroelectric_power_st...
According to the Hydrology Department of Henan Province, approximately 26,000 people died in the province from flooding and another 145,000 died during subsequent epidemics and famine. In addition, about 5,960,000 buildings collapsed, and 11 million residents were affected. Unofficial estimates of the number of people killed by the disaster have run as high as 230,000 people. The death toll of this disaster was declassified in 2005.
See: https://www.ucsusa.org/clean_energy/our-energy-choices/renew...