Jacuí River

The Jacuí River is a river in Rio Grande do Sul state of southern Brazil. The Jacuí empties into the Guaíba River, an estuarine arm of the Lagoa dos Patos, a large coastal lagoon connected to the Atlantic Ocean.

Regional effects
The Dona Francisca Hydroelectric Dam impounds the upper Jacuí River, and is divided between the municipalities of Agudo and Nova Palma, Rio Grande do Sul. The Quarta Colônia State Park is on the left bank of the reservoir of the Dona Francisca dam, with an area of 1847.9 ha. The park was created in 2005 as environmental compensation for the hydroelectric plant.

The estuary contains the Banhados do Delta Biological Reserve, which protects the islands of Pólvora and Pombas.