For the formation of the Itaipu reservoir, an area of approximately 100,029 hectares was expropriated, including the municipalities of Foz do Iguaçu, São Miguel do Iguaçu, Medianeira, Santa Helena, Matelândia, Marechal Cândido Rondon, Terra Roxa and Guaíra. In this process, 19 indigenous families were located and registered by the National Indian Foundation (Funai), totaling 71 people of the Ava Guarani ethnic group, who occupied an area of approximately 30 hectares. In order to accommodate these families, the Ocoy Indigenous Reserve was created in 1982 with technical and financial support from Itaipu, in São Miguel do Iguaçu, with an area of 250 hectares.

In 1997, due to the vegetative and migratory growth of the Ocoy population, Itaipu and Funai entered into an agreement to establish the Tekoha Añetete village in Diamante D'Oeste, with an area of 1,744 hectares. In addition to the Indigenous Reserves of Ocoy and Añatete, the Sustainability of Indigenous Communities program (see more on page 73) also supports the Tekoha Itamarã village, established in 2007, with an area of 242 hectares, bordering Tekoha Añatete, acquired by Funai after negotiations between indigenous and the Foundation.