The Ecomuseu de Itaipu tells the human and environmental story behind the dam — a story that the dam's official tours tend to skip over. The museum occupies a building near the dam's administrative complex and covers the archaeology of the region before the reservoir was created, including the indigenous Guaraní communities whose lands were flooded, and the history of the city of Guaíra, which was partially submerged.
The centrepiece of the collection is the story of the Salto das Sete Quedas, a series of massive waterfalls on the Paraná River that were submerged when the reservoir filled in 1982. Once considered the most powerful waterfall in the world by volume, the Seven Falls were deliberately dynamited after flooding to prevent navigational hazards. The destruction was controversial and remains a sore point in Brazil's environmental history. Photographs and footage in the museum give some sense of what was lost.