Reservatório Xingó is a large hydroelectric reservoir located on the lower São Francisco River, straddling the border region of Alagoas and Sergipe in northeastern Brazil. Created by the Xingó Hydroelectric Power Plant (HPP), which began operations in 1994 as the final dam in a cascade of hydroelectric projects developed along the São Francisco River since the 1950s, the reservoir sits within a dramatic canyon landscape carved through ancient crystalline rock. The surrounding semi-arid caatinga biome gives the region a rugged, striking character, with steep canyon walls dropping to the reservoir's clear, greenish waters. The reservoir has become an important fishery in the region, supporting both subsistence and recreational fishing communities, though its ecology has shifted considerably since impoundment.