 The basin of the Piabanha River includes the basins of the upper Piabanha, Preto, Fagundes and Paquequer rivers.It fully drains the municipalities of Teresópolis, Carmo, Sapucaia, Sumidouro, Areal and São José do Vale do Rio Preto, and partially drains the municipalities of Petrópolis, Paty do Alferes, Paraíba do Sul, Duas Barras and Três Rios.The headwaters of the river are protected by the Três Picos State Park, Serra dos Órgãos National Park, Petrópolis Municipal Nature Park, Montanhas de Teresópolis Municipal Nature Park, Araras State Biological Reserve and Araponga Municipal Nature Park among others.