
Image from National Archives and Records Administration NARA.gov
The 1953 dedication of Falcon Dam created a massive reservoir on the Rio Bravo del Norte, aka Rio Grande. Farmers and villagers were displaced on both sides of the river.
A city on the Mexican side was flooded, the inhabitants relocated to new homes built for them by the Mexican government.

Towns and farms on the U.S. side were also flooded, the inhabitants had to sue for relocation assistance and compensation, resolved — perhaps not equitably — years afterwards.
Reference: U.S. Congressional hearings on the dam.