The River Plate Basin is formed by the Parana, Uruguay and Paraguay rivers, which flow from Brazil and create the River Plate in the border area between Argentina and Uruguay.
One of the features of this basin is the Guarani aquifer, one of the largest known underground water reservoirs in the world, with an area of 1,6 million km 2 and volume of 40,000 km 3. The aquifer is shared by Argentina, Brazil, Paraguay and Uruguay.
The basin comprises a vast area in Argentina, Uruguay, Paraguay, and southern parts of Brazil and Bolivia.
In April 1969, the five countries signed the Treaty of the River Plate Basin, where they agreed to work together to promote the balanced and harmonious development of the area, as well as the rational use of its natural resources, assuring the preservation of the system for future generations.