 At Porto Alegre, near the Atlantic coast, the Jacuí transforms into a shallow estuary, known as the Guaíba River, and flows into the Patos Lagoon.Boats can travel up the river as far as Cachoeira do Sul.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.