a river in South America, in northwestern Argentina. It is approximately 650 km long. Originating as the Salí in the Andes, in the Sierra del Aconquija, the Dulce flows over the southern part of the dry Gran Chaco plains, often branching out into arms, and empties into Lago Mar Chiquita. There are flash floods in the summer, and the water level is low during the winter. The mean flow rate where the Dulce emerges from the mountains is approximately 80 cu m per sec; the rate does not increase further downstream because of the volume of water taken for irrigation. The city of Santiago del Estero is on the Dulce.