The Lauca River is a binational river. It originates in the Chilean Altiplano of the

Arica and Parinacota Region The Arica y Parinacota Region ( es, link=no, Región de Arica y Parinacota ) is one of Chile's 16 first order administrative divisions. It comprises two provinces, Arica and Parinacota. It borders Peru's Department of Tacna to the north, Bolivia ...

, crosses the Andes and empties into

Coipasa Lake __NOTOC__ Lago Coipasa or Salar de Coipasa is a lake in Sabaya Province, Oruro Department, Bolivia. At an elevation of 3657 m, its surface area is 806 km². It is on the western part of Altiplano, 20 km north of Salar de Uyuni and south o ...

Bolivia , image_flag = Bandera de Bolivia (Estado).svg , flag_alt = Horizontal tricolor (red, yellow, and green from top to bottom) with the coat of arms of Bolivia in the center , flag_alt2 = 7 × 7 square p ...

. The upper reach of the river lies within the boundaries of Lauca National Park in the

Parinacota Province Parinacota Province ( es, Provincia de Parinacota) is one of two Provinces of Chile, provinces of the Chilean Regions of Chile, region of Arica y Parinacota Region, Arica y Parinacota. Its capital is Putre. It is named after the Parinacota Volcano ...

. Lauca River receives waters from a group of lakes known as Quta Qutani through the ''Desaguadero River''. In this area there is a type of marsh known as Parinacota wetlands, in which converge several streams, being the more important the river just mentioned, which has a variable flow rate ranging from 100 to 560 L/s, and an average of 260 L/s. From its source in the Parinacota wetlands the river flows west. The spurs of the ''Cordillera Central'' (also known as ''Chapiquiña'') form an obstacle impossible to pass through, forcing the river's course southward. In the vicinity of

Wallatiri Guallatiri is a high volcano in Chile. It is located southwest of the Nevados de Quimsachata volcanic group and is sometimes considered to be part of that group. It is a stratovolcano with numerous fumaroles around the summit. The summit may be ...

volcano, the Lauca turns again, now eastward crossing from Chile into Bolivia at the latitude of ''Macaya'', at an elevation of 3,892 m asl and with a flow rate about 2,6 m³/s. In Chile the river drains an area of 2,350 km².Cuenca del río Lauca
In the Bolivian Altiplano, the Lauca collects the waters of the rivers Sajama and Coipasa, raising its flow rate up to 8 m³/s before turning south to empty into Coipasa Lake, close to the salt flat of the same name. During the 1930s, the Chilean government begun to use the hydrical resources of Lauca river for irrigation in the Azapa Valley, generating a complaint from Bolivian government who argued that Chilean authorities were altering the course of an international river. Chile answered that the natural course of the river was not modified, but the works executed were related to the use of waters in the Parinacota wetlands, which not affect the total water flow of the Lauca in its course to Bolivia. The litigation between both countries, started in 1939, caused diplomatic tension until the 1960s.TERENCE R. LEE
The Management of Shared Water Resources in Latin America
page , retrieved on 15 June 2012

References

*This article draws heavily on the corresponding article in the Spanish-language Wikipedia, accessed March 31, 2007. * {{DEFAULTSORT:Lauca Rivers of Bolivia Rivers of Oruro Department Rivers of La Paz Department (Bolivia) Rivers of Chile Rivers of Arica y Parinacota Region Rivers of Tarapacá Region International rivers of South America