Amazon River

• Treaty for Amazonian Co-operation. Done at Brasilia, 3 July 1978. Bolivia, Brazil, Colombia, Ecuador, Guyana, Peru, Suriname, Venezuela

Parana River Basin

• Argentina-Brazil-Paraguay: Agreement on Parana River Projects (1979)
• Treaty of Yacyreta. Signed at Asuncion on 3 December 1973
• Treaty Between the Federative Republic of Brazil and the Republic of Paraguay Concerning the Hydroelectric Utilization of the Water Resources of the Paraná River Owned in Condominium by the Two Countries, From and Including the Salto Grande de Sete Quedas or Salto Del Guaira, to the Mouth of the Iguassu River (1973)
• Agreement Between The Argentine Republic and the Republic of Paraguay Concerning a Study of the Utilization of the Water Power of the Apipe Falls, Done at Buenos Aires, 23 January 1958

Rio Pilcomayo

• Agreement constituting the Trinational Commission for the Development of the Pilcomayo River Basin. Done in La Paz, 9 February 1995 (Spanish)
• Supplementary boundary treaty between the Argentine Republic and the Republic of Paraguay on the River Pilcomayo and Protocol annexed to the treaty. Signed at Buenos Aires 1 June 1945
• Supplementary boundary treaty between Argentina and Paraguay. Signed at Buenos Aires 5 July 1939

Plata River Basin

• Treaty of the River Plate Basin. Signed at Brasilia on 23 April 1969; Came into force on 14 August 1970. Brazil, Argentina, Bolivia Paraguay and Uruguay
• Treaty between Uruguay and Argentina concerning the Rio de la Plata and the Corresponding Maritime Boundary, signed in Montevideo on 19 November 1973
• Agreement Concerning Hydraulogic Basins, Argentina & Chile (1971) 64 L.N.T.S. 113
• Protocol between Uruguay and Argentina dealing with the question of the jurisdiction of the River Plate. Signed at Montevideo, 5 January 1910; 5 January 1910

Uruguay River

• Agreement by exchange of notes between the Argentine Republic and the Eastern Republic of Uruguay concerning the establishment of a scientific committee within the Administering Commission of the Uruguay River. Done in Buenos Aires, 30 August 2010; in force 30 August 2010
• Agreement signed by the Presidents of the Argentine Republic and of the Eastern Republic of Uruguay for the joint monitoring of the BOTNIA UPM PULL plant and all the industrial and agricultural establishments and urban centres that discharge their effluents into the River Uruguay and the areas affected by it. Done in Buenos Aires, 28 July 2010; in force 28 July 2010
• Statute of the River Uruguay. Signed at Salto on 26 February 1975
• Treaty between the Argentine Republic and the Eastern Republic of Uruguay on the boundary constituted by the Uruguay River. Signed at Montevideo, 7 April 1961.
• Agreement Concerning the Utilization of the Rapids of the Uruguay River in the Salto Grande Area. Signed at Montevideo 30 December 1946; in force 28 January 1947

Guarani Aquifer

• Agreement on the Guarani Aquifer, done in San Juan, Argentina, 2 August 2010 (not in force) [Portuguese] [Spanish] [English (unofficial)]

• Act of Asunción on the Use of International Rivers of 3 June 1971. Argentina, Bolivia, Brazil, Paraguay, Uruguay