The Cachoeira do Cai Dam (Portuguese: Barragem de Cachoeira do Cai) is a planned hydroelectric dam on the Jamanxim River in the state of Pará, Brazil, with a capacity of 802 megawatts (1,075,000 hp).

[1] It would adjoin the Sawré Muybu Indigenous Territory, which lies between the Jamanxim and the Tapajós in the region above the point where the two rivers converge.

[4] The project is a joint venture of Eletrobras, Eletronorte, Construções e Comércio Camargo Côrrea, EDF Consultoria em Projetos de Geração de Energia, EPP Energia Elétrica and Promoção e Participações.

[1] A "platform" approach is proposed for construction to minimise environmental impact.

[1] A study released in December 2015 took into account carbon and methane emissions from the reservoir and from construction and concluded that there was a high probability that the plant would generate emissions comparable to a natural gas plant, and a possibility that emissions could exceed those of a coal-fired plant.