The project had a massive ecological and social impact on the region. People who lost their homes and farms to the lake, were still not re-settled or compensated almost 20 years after it was formed, it displaced native peoples from their ancestral lands, drowned old growth forests which caused them to rot and release CO2 and methane, disrupted the reproductive cycle of several species of fish, towns that were far from the river and then were close to the expanded lake were inundated by mosquitos, I could go on.
But hey, progress right ?
Fucking dictatorship.
Itaipu was completelly unneccessary, A chain of smaller dams would have provided the same capacity, but with lower and more distributed impact, but the fucking dictators had to show how Brazil was capable of tackling huge engineering projects.